Chicken and Red Bean Tostadas

I cut this recipe out of a magazine, but the part of the page I have doesn't say which one...All You, maybe? Anyway, I have been having these for lunch the past couple days and really am in love with them. It's just a tostada, so you don't really need a recipe, but I liked that this particular version had you put them in the oven to melt the cheese over the meat and beans. You could mix these up with any variety of meat, beans, cheese and have a whole different taste. They are a little messy to eat though...probably not the best thing to eat in front of others :-).

Ingredients:
4 10-inch flour tortillas (I bought some pre-made tostadas made from corn tortillas)
2 T vegetable oil
3 grilled chicken breast halves, chopped (I used leftover chicken and shrimp)
1 15-oz. can red beans, drained and rinsed
1 1/2 cups shredded Monterey Jack (I used pepper jack)
4 cups shredded romaine lettuce (from 1 head)
1 1/2 cups tomato salsa (I have been using my Creamy Avocado Salsa)
1/2 cup low-fat sour cream

Directions:
Arrange racks in top and bottom thirds of oven and preheat to 400ºF. Line 2 large baking sheets with foil. Place tortillas on baking sheets and brush with oil. Bake until lightly browned, 4 to 5 minutes. (skip this if you get the pre-made shells like me)
Divide chicken, beans and cheese among tortillas and return to oven. Bake until cheese has melted, 3 to 4 minutes. Remove from oven, top each portion with 1/4 of lettuce, salsa and sour cream. Serve immediately.