Grilled Mushroom and Walnut Patties with Caramelized Onion Aioli

By AislePrompt Editorial · Published 2026-04-09 · Updated 2026-04-09

Savory plant-based patties with earthy mushrooms and toasted walnuts, grilled until crisp and served with a sweet-savory aioli made from deeply caramelized onions. This American vegetarian recipe, ready in about 55 minutes, pairs cremini mushrooms, walnuts, and breadcrumbs for a weeknight-friendly dinner. Each serving lands at about 385 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 "Build a week of meals around this recipe" 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.

Ingredients

• 8 oz cremini mushrooms
• 1/2 cup walnuts
• 1/4 cup breadcrumbs
• 1 large egg
• 1 tbsp olive oil
• 1/2 tsp dried thyme
• 1/2 tsp garlic powder
• to taste salt
• to taste black pepper
• 1 small onion
• 1/2 tsp honey
• 1/2 cup plain yogurt
• 2 cups arugula
• 4 burger buns

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Instructions

1. Step 1: Combine 8 oz finely chopped cremini mushrooms, 1/2 cup toasted and chopped walnuts, 1/4 cup breadcrumbs, 1 large egg, 1 tbsp olive oil, 1/2 tsp dried thyme, 1/2 tsp garlic powder, and salt and pepper to taste in a bowl. Mix until evenly incorporated, then form into 4 equal patties.
2. Step 2: Heat a grill pan over medium-high heat. Lightly oil the surface. Place patties on the grill and cook for 4-5 minutes per side until golden brown and heated through.
3. Step 3: In a small skillet, heat 1 tbsp olive oil over medium heat. Add 1 finely sliced small onion and cook, stirring occasionally, for 15-20 minutes until deeply golden and caramelized. Stir in 1/2 tsp honey, salt, and pepper, then remove from heat and let cool.
4. Step 4: Mix the cooled caramelized onions with 1/2 cup plain yogurt in a small bowl. Season with salt and pepper to taste.
5. Step 5: Toast the burger buns if desired. Place a grilled patty on each bun, top with 1/2 cup arugula, and drizzle with the caramelized onion aioli.