Preheat oven to 350. Warm flour tortillas in the microwave (wrap them in a dish towel in batches of 4), or in the oven (wrap them, 4 at at a time, in foil and warm for 15-20 minutes). Meanwhile, heat refried beans in a saucepan over medium heat, grate cheeses together, and mince green onions.
When tortillas are warm, fill each one down the middle, stopping about an inch before the bottom edge, with 1/2 cup of the beans, 1/4 cup of the cheeses, and minced green onion and/or minced jalapenos to taste.
Fold up bottom of tortilla, then roll it over to form a tube. Put rolled tortillas on baking sheet, seam side down, and bake about 5 minutes.
Garnish with sour cream and salsa, if desired.