1. Preheat oven to 350 degrees. Spray 9 x 13 inch pan with Pam.
2. Empty the cans of black and kidney beans into a colander and drain. Rinse the beans under cold running water and drain again. Place all the beans (including the baked beans or pork and beans) in a large nonreactive mixing bowl and add the onion, red and green bell peppers, garlic, and jalapenos, and stir to mix. Add the barbecue sauce, brown sugar, mustard, and fried bacon and stir to mix. Taste for seasoning, adding more brown sugar and/or mustard if necessary, and salt and black peper to taste; the beans should be very flavorful. Transfer the bean mixture to the prepared pan.
3. Bake for 3 hours, uncovered, stirring occasionally until thick.