1.  Trim excess fat from pork.  Place pork roast in slow cooker.  Sprinkle with chili powder, cumin and hot pepper flakes.  Add canned tomatoes (drained) and green chilies (including liquid).

2.  Cover and cook on low for 8-10 hours or high for 4-5 hours, until pork is tender.

3.  Transfer pork to a bowl, and using two forks, pull meat into shreds.  Skim fat from sauce.  Return meat to sauce in slow cooker.

4.  Heat refried beans in microwave.  Heat taco shells according to package directions.

5.  Spread tortillas with a spoonful of hot refried beans.  Set 1 taco shell in center.  Fold flour tortilla around taco shell.  Spoon about 1/3 cup pork mixture into each taco shell.  Top with cheese, lettuce, tomatoes and sour cream.