Ingredients
2 tablespoons extra-virgin olive oil
1 medium yellow onion, halved and cut into 1/4-inch slices
10 ounces mushrooms, such as button or cremini, trimmed and sliced
Coarse salt and ground pepper
1 can (15 ounces) diced tomatoes with green chiles, such as Ro-Tel, drained
8 tostada shells
3 cups diced or shredded cooked chicken (about 3/4 pound)
Shredded romaine lettuce, shredded Monterey Jack or crumbled Cotija cheese, and sour cream, for serving
Preparation
In a large skillet, heat oil over medium-high. Add onion and cook 4 minutes. Add mushrooms and cook, stirring occasionally, until onion is softened and mushrooms are golden brown, about 6 minutes. Season with salt and pepper. Add tomatoes with chiles and cook, stirring, until warmed through, about 2 minutes.
Spread tomato mixture on tostada shells. Top with chicken, lettuce, cheese, and sour cream.
