12 flat hard shell corn tortillas (tostada size)
1 tablespoon vegetable oil
1 red onion, thinly sliced
2 cups mushrooms, thinly sliced
2 carrots, sliced as thin as possible
1 medium zucchini, thinly sliced
Kosher salt and fresh ground pepper to taste
1 1/2 cups low-fat jack cheese (or your favorite), grated
1 cup homemade vegetable salsa (or your favorite store-bought)
1/4 cup low fat sour cream
1/2 cup scallions, chopped
Pre-heat oven to 400 degrees. Heat oil over medium-high heat in a large sauté pan. Add onion and sauté, stirring frequently for 3 to 4 minutes. Add all other vegetables and continue cooking, stirring occasionally, until vegetables are crisp-tender, about 5 minutes. Remove from heat and season with salt and pepper.
Place four tortillas on baking sheet. Evenly distribute spoonfuls of the sautéed vegetables on each tortilla, than add a small amount of the cheese. Repeat so that you have four stacks with three tortillas each. Make sure to save some cheese for the top of the last layer.
Bake for 6 to 10 minutes until the stacks are heated thoroughly. Garnish the top of each stack with salsa, sour cream and scallions. Serve warm.