Preheat oven to 425 degrees.
Saute onion and add ground beef in a skillet.
Cook until no longer pink (approx 7-10 mins).
Take off heat and drain.
Stir in refried beans, salsa and cheese after cool for a minute.
Melt butter and brush on tortillas, both sides. Wax paper can be used for less mess.
Spoon about 1/4 c. of beef mix into the center of the tortilla.
Fold sides over tortilla, like a burrito.
Place on baking sheet, seam side down.
Make sure to space them out so they are not touching.
Bake for 5-7 minutes per side or until golden brown.
Optional - sprinkle with additional cheese and return to oven to melt cheese (watch closely to avoid burning them).
Serve with favorite toppings - Sour cream, lettuce, olives, additional cheese, tomatoes, guacamole, etc.