Quick Overview
- Dish: Baked portobello mushroom caps filled with a light, lump crabmeat stuffing
- Flavor Profile: Sweet crab balanced by earthy mushrooms, lemon, thyme, and mild melted cheese
- Key Technique: Pre-baking the mushroom caps prevents excess moisture from watering down the filling
- Method: Mushroom caps are pre-baked, filled with crab stuffing, then baked until golden
- Servings: 4
- Total Time: 45 minutes
- Effort Level: Simple
A Lighter Take on Crab Stuffed Mushrooms
These crab stuffed portobello mushrooms are the kind of seafood recipe that works equally well for a casual dinner at home or an easy appetizer for entertaining. Pre-baking the mushroom caps keeps them from turning watery, while the flavor of the filling stays focused on sweet lump crabmeat accented with garlic, thyme, lemon, and just enough cheese to hold everything together.
We developed this recipe as a lighter alternative to traditional crab-stuffed mushrooms that can sometimes feel overly rich or breadcrumb-heavy. The portobello caps add enough substance to serve as a light seafood dinner when served with a simple vegetable or salad, but the smaller portions also fit naturally into a dinner party menu or holiday appetizer spread.
Ingredient Notes and Substitutions
A few key ingredients make this recipe work – here’s what to know. A complete list with quantities is in the recipe card below.
- Lump crabmeat: Pasteurized lump crabmeat has a delicate, sweet flavor and tender texture that works well in this filling. Be gentle when mixing so the larger pieces stay intact, and plan to use any leftovers within 2 days of opening.
- Portobello mushroom caps: When shopping, choose firm mushroom caps with even color and minimal moisture. Pre-baking them before stuffing helps release excess liquid and keeps the filling from becoming watery.
- Mild shredded cheese: Muenster or Monterey Jack melt smoothly without overpowering the crab. Avoid sharper cheeses like cheddar, which can dominate the filling.
- Panko breadcrumbs: Panko keeps the stuffing light and helps absorb moisture without making the filling dense.
- Fresh lemons: Lemon juice brightens the crab filling, and serving the mushrooms with lemon wedges adds fresh contrast to the rich seafood and cheese.
- Fresh thyme: Thyme adds a subtle earthy note that pairs naturally with both crab and mushrooms. Fresh thyme is preferred, but dried thyme works in a pinch.
A Quick Look at Preparation
Crab-Stuffed Portobello Mushrooms with Lemon & Thyme
Here’s how this dish comes together, along with a few tips for the best results. Full instructions are in the recipe card below.
The key to good crab stuffed portobello mushrooms is removing excess moisture before adding the filling. Start by removing the stems and gills from the mushroom caps, then give them a quick pre-bake. Once they soften slightly, blot away any liquid they release.
While the mushrooms bake, prepare the filling by combining the chopped mushroom stems with lump crabmeat, panko, onion, garlic, thyme, lemon juice, cheese, and egg. Mix gently so the crab stays in larger pieces rather than breaking down into a paste. The filling should hold together lightly without feeling dense.
Once stuffed, the mushrooms are baked until the filling is heated through and lightly golden around the edges. A final layer of melted cheese adds richness, while lemon wedges served alongside brighten the flavors and balance the earthy mushrooms and sweet crab.
Tested Tip for Better Texture
Mushrooms naturally release water as they cook, particularly large portobellos. Pre-baking the caps before stuffing allows some of that moisture to evaporate and gives you a chance to blot away the rest. It’s a simple step, but it makes a noticeable difference in keeping the filling light instead of soggy.
Make-Ahead Notes
You can prepare the crab filling up to a day in advance and refrigerate it tightly covered until ready to use. For the best texture, wait to stuff and bake the mushrooms until shortly before serving.
The mushroom caps can also be cleaned and pre-baked ahead of time. Once cooled, blot away any remaining moisture and refrigerate them separately from the filling.
If you need to fully assemble the mushrooms in advance, you can refrigerate them for a few hours before baking. Let them sit at room temperature briefly before putting them in the oven so they heat evenly.
More Easy Crab Recipes to Try
If you enjoy these crab stuffed portobello mushrooms, try our Maryland-Style Baked Crab Cakes, crisp-edged crab cakes with a light breadcrumb coating and balanced seasoning; Crab Louie Salad, a classic composed seafood salad with crisp vegetables and tangy dressing; or Linguine with Lump Crabmeat, a simple pasta tossed with crab, tomatoes, garlic, and white wine butter sauce.
Crab-Stuffed Portobello Mushrooms
Ingredients
- 4 portobello mushroom caps, 3-1/2 to 4" diameter
- Salt and freshly ground black pepper
- 8 oz lump crabmeat, fully-cooked, pasteurized
- 1/2 cup panko crumbs
- 2 tablespoons chopped sweet onion
- 1 or 2 cloves garlic, minced
- 1 teaspoon fresh thyme leaves, (or 1/4 teaspoon dried)
- 1-1/2 tablespoons freshly squeezed lemon juice, from 1/2 lemon
- 2/3 cup shredded Muenster or Monterey Jack cheese, divided
- 1 egg, lightly beaten
- Lemon wedges, for serving
Instructions
- Preheat the oven to 375°F and coat a sheet pan with nonstick spray.
- Remove the stems from the portobello caps and finely chop them. Using a spoon, gently scrape out the dark gills and wipe the caps clean with paper towels.
- Arrange the mushrooms gill side up on the prepared pan and season lightly with salt and pepper. Bake for 8 minutes, then carefully blot away any liquid released by the mushrooms with paper towels. Set aside.
- While the mushrooms pre-bake, combine the chopped mushroom stems, crabmeat, panko, onion, garlic, thyme, lemon juice, and all but 2 tablespoons of the cheese in a mixing bowl.
- Season the mixture lightly with salt and pepper, then fold in the beaten egg just until combined. Be careful not to break up the crabmeat too much.
- Divide the filling among the mushroom caps, gently pressing it into place and mounding it slightly on top.
- Bake for 10 to 12 minutes, until the filling is heated through and lightly golden around the edges.
- Top the mushrooms with the reserved cheese and return to the oven for 2 to 4 minutes, until melted and bubbly.
- Serve hot with lemon wedges and hot sauce if desired.
Notes
Nutrition
Nutrition information is automatically calculated, so should only be used as an approximation.
What grocery stores can you buy full portabello mushrooms at?
Hi Kelsea,
I’ve seen whole portobello mushrooms (stem included) at Whole Foods Market, but portobello caps, which is what this recipe calls for should be available in the produce section of most local grocery stores.
This recipe was delicious. I served these with a creamy horseradish dip on the side to give it a zing.
Thanks for the recipe.
I’m traveling on Thanksgiving and I can’t cook until I get to my destination . Can I precooked the mushrooms the night before? Or will the mushrooms become soggy?
Hi Neff,
That’s a good question! All mushrooms give off liquid as they cook, so if you’re not going to serve them right away, I would pre-bake the portobello caps to get them to release some of that liquid before you add stuffing. Up the oven temperature to 400°F, lightly salt the inside of the portobello caps, and bake for 5 to 7 minutes. When you take them out of the oven, blot any liquid that pools in the center with paper towels and let them cool down before adding the stuffing. Lower the oven temp back to 375°F and bake until the crab mixture is set and just beginning to brown. Let them cool completely before refrigerating so they don’t give off steam. This should prevent the stuffing from getting soggy. Reserve the extra cheese for when you’re ready to reheat and bring them to room temperature before popping them into a 400°F oven for 6 to 10 minutes. You’ll need to keep a watchful eye. Hope this helps!
Can I substitute Mozzarella cheese instead of Muenster or Jack? I have never made stuffed crab before which at my age who loves trying new dishes is a shocker. I can’t let my husband think that I stopped experimenting lol
Hello!
These look fantastic. I was wondering though how many ounces for each mushroom? I found a 2 pack and they are about 7 oz each. Are those the ones you used?
Hi Nicole,
Most portobello mushroom caps weigh 3 to 3-1/2 ounces each, so yes, you absolutely have the right size.
Hi, weird question but any way to do on the stove top with a grill pan? I bought all the ingredients but my oven broke..
Hi Kimberly,
Truthfully I think you’d be better off with a regular frying pan than a grill pan, but here’s what I think you could try:
Brush your frying or grill pan with a little oil, add your portobello caps and cook over medium-high heat for about 2 minutes per side to tenderize them, then set aside.
Combine the remaining ingredients and form the mixture into crab cakes that are about the diameter of your mushrooms. Add some more oil to the pan and fry them until golden, maybe 2 minutes per side. The tricky part here is keeping the crab mixture holding together as a crab cake. If they don’t stick and you’re careful turning them it should work out.
Once they’re lightly browned, carefully press them into the mushroom caps, then put them back in the pan, filling side up. Add a little extra cheese on top, cover the pan and cook over medium heat for another 3 minutes or so.
Good luck!
Do you publish a cookbook?
Hi Kevin,
We don’t publish a cookbook at this time, but all our recipes are easily printable. Thanks for asking!
My husband and I loved this recipe. Next time I plan on adding some Dijon mustard. Thank you for sharing.
Hi Judi,
Glad to hear you liked the recipe. I think adding Dijon is a great idea. It would blend nicely with the lemon and add a little extra punch. Thanks!
Wish you had given size of the mushrooms..
Hello Holly,
Sorry for that omission. Most portobello mushrooms are about four inches in diameter.
It was fabulous, big hit with even my husband who doesn’t like cooked mushrooms. We made on the BBQ – too hot for oven. Thankyou!!