Ingredients
1 large sweet onion, thinly sliced2 tablespoons olive oil1 tablespoon butter3 garlic cloves, minced1/4 teaspoon salt1/4 teaspoon pepper1 package (17.3 ounces) frozen puff pastry, thawed1 cup shredded Gruyere or Swiss cheese1/4 cup grated Parmesan cheese2 tablespoons minced fresh thyme
Preparation
In a large skillet, saute onion in oil and butter until softened. Reduce heat to medium-low; cook, uncovered, for 40 minutes or until deep golden brown, stirring occasionally. Add garlic; cook 1 minute longer. Stir in salt and pepper.
Unfold each puff pastry sheet onto an ungreased baking sheet. Using a knife, score decorative lines around the edges of each sheet. Spread onion mixture to within 1/2 in. of edges. Sprinkle with cheeses and thyme.
Bake at 400° for 12-15 minutes or until golden brown. Cut each tart into 12 pieces. If desired, top with additional fresh thyme and Parmesan cheese. Serve warm.
