Potato, Mushroom, and Leek Croquettes

By TPMay

Ingredients

• 8 ounces coarsely chopped peeled Yukon gold potato
• 4 ounces sliced cremini mushrooms
• 4 ounces sliced button mushrooms
• 1/2-cup chopped leek
• 1 teaspoon chopped fresh thyme
• Cooking spray
• 1/2-cup (2 ounces) shredded Gruyere cheese
• 1/4-cup (1 ounce) grated Parmigiano-Reggiano cheese, divided
• 1/2-teaspoon kosher salt
• 1/2-teaspoon freshly ground black pepper
• 1 large egg yolk
• 1/3 cup all-purpose flour
• 1 large egg white
• 2 teaspoons water
• 1/2-cup panko (Japanese breadcrumbs)
• 1 tablespoon olive oil

Preparation

Step 1

Place potato in a pan; cover with water. Bring to a boil. Reduce heat; simmer 8 minutes or until tender. Drain. Press potato through a ricer or food mill into a bowl.
Place mushrooms, leek, and thyme in a food processor; pulse until finely chopped. Heat a large skillet over medium heat. Coat pan with cooking spray. Add mushroom mixture; cook 6 minutes, stirring occasionally. Add mixture to potato. Add Gruyère, 2 tablespoons Parmigiano-Reggiano, salt, pepper, and egg yolk; stir until blended. Shape mixture into 8 (2-inch) round patties.
Place flour in a shallow dish. Combine egg white and 2 teaspoons water in a shallow dish, stirring with a whisk. Combine remaining 2 tablespoons Parmigiano-­Reggiano and panko in a shallow dish. Dredge patties in flour. Dip in egg mixture; dredge in panko mixture. Heat a large nonstick skillet over medium-high heat. Add oil; swirl to coat. Add patties; cook 4 minutes on each side or until golden.