Cheddar and Spinach Stuffed Portobello Mushrooms

By AislePrompt Test Kitchen · Reviewed by AislePrompt Editorial · ·

Large Portobello mushroom caps filled with a savory mixture of cheddar cheese and sautéed spinach, baked to a golden, bubbly finish. This american-inspired keto (keto, vegetarian) ready in about 30 minutes pairs chopped fresh spinach, shredded sharp cheddar cheese, softened cream cheese for a weeknight-friendly dinner that comes together with one pan and minimal cleanup. Each serving lands at about 250 calories and feeds 4, so it slots cleanly into a weekly meal plan and pairs well with a quick salad or grain on the side. Tap "Plan a meal with the AI" below to drop this recipe into your week and send the ingredients straight to Instacart. Nutrition values are approximate, calculated from USDA FoodData Central (fdc.nal.usda.gov) — verify against ingredient labels for any health-driven dietary plan.

Prep: 10 min Cook: 20 min Serves 4 American cuisine 250 cal/serving
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Ingredients

Instructions

  1. Step 1: Preheat oven to 400°F. Brush 4 large Portobello mushroom caps with 1 tbsp olive oil and sprinkle each with 1/2 tsp salt and 1/4 tsp black pepper. Place caps on a baking sheet gill side up.
  2. Step 2: Heat remaining 1 tbsp olive oil in a skillet over medium heat. Add 3 minced garlic cloves and sauté for 30 seconds until fragrant. Add 5 oz chopped fresh spinach and cook for 3-4 minutes until wilted and excess moisture evaporates. Season with 1/2 tsp salt, 1/4 tsp black pepper, and 1/4 tsp red pepper flakes if using.
  3. Step 3: Remove skillet from heat and stir in 4 oz softened cream cheese until combined. Fold in 1 cup shredded sharp cheddar cheese, reserving a small handful for topping.
  4. Step 4: Spoon the spinach and cheese mixture evenly into each mushroom cap, then sprinkle the remaining cheddar cheese on top.
  5. Step 5: Bake in the preheated oven for 15-18 minutes until the mushrooms are tender and the cheese is melted and golden. Serve warm as a hearty keto appetizer or side.

Frequently asked questions

How long does Cheddar and Spinach Stuffed Portobello Mushrooms take to make?

Total time is about 30 minutes (10 min prep + 20 min cook). Most home cooks find this fits comfortably into a weeknight; double the batch on Sunday for two dinners.

How do I store leftover Cheddar and Spinach Stuffed Portobello Mushrooms?

Cool to room temperature within 2 hours, then store in an airtight container in the fridge for up to 4 days. Reheat covered in a 350°F oven for 10-12 minutes, or microwave at 70% power in 60-second bursts to keep chopped fresh spinach from drying out.

Can I substitute ingredients in Cheddar and Spinach Stuffed Portobello Mushrooms?

Yes — most ingredients in this recipe have flexible swaps. For oil, use any neutral high-smoke-point oil (avocado, grapeseed, refined coconut). For aromatics, dried herbs at ⅓ the volume of fresh work in a pinch. The full ingredient list is shoppable on Instacart so you can see substitutes in real time.

How do I scale Cheddar and Spinach Stuffed Portobello Mushrooms for a different number of people?

The recipe is written for 4 servings. Multiply each ingredient by (your serving target / 4). Cook time stays roughly the same up to 2x; for 3-4x batches, switch from a skillet to a sheet pan or stockpot so the food isn't crowded — overcrowding steams instead of browns.

Is Cheddar and Spinach Stuffed Portobello Mushrooms keto?

Yes — this recipe is tagged keto, vegetarian, gluten free, low carb based on its ingredient list. Always cross-check labels for packaged ingredients (sauces, broths, condiments) since formulations vary by brand.

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