Tacos - cooking recipe

Ingredients

1 1/2 lb. ground beef
1 chopped onion
1 can chili beans (optional)
1 (8 oz.) can tomato sauce
1 1/2 tsp. chili powder
1/2 tsp. paprika
1/2 tsp. oregano
1/4 tsp. pepper
1 tsp. salt
1/4 tsp. rosemary (rub together in your fingertips before adding)
2 Tbsp. Worcestershire sauce
precooked tortilla shells (or fry your own)

Preparation

Brown the beef and the onion in a heavy skillet, cutting the meat in very small pieces.
Add the rest of the ingredients (except the tortilla shells) and slowly simmer for 1 hour (can be 30 minutes but the longer it cooks, the better).
Fill the tortilla shells with this mixture and serve.