If meat is not already pounded out with a meat mallet, pound meat down to ⅛-inch thick. (This same process could be applied to a chuck roast and left whole)
In a shallow plate or dish, combine flour, seasoning salt, black pepper, 1 teaspoon paprika, and garlic powder.
Dip each side of meat in the flour mixture and place in a skillet on medium heat.
Sear each side of meat and remove from skillet to a plate. Repeat for all pieces of meat.
Pour bag of frozen peppers and onions in bottom of crockpot.
Add carrots and celery if using those vegetables.
Place meat on top of peppers and onions.
While skillet is still hot, pour in 1 cup of water to deglaze skillet. Stir quickly, removing all the bits off the bottom of the pan.
Add additional ½ cup water, bullion, Worcestershire, minced garlic, and 1 teaspoon paprika. Stir together.
Whisk in 1 teaspoon of the leftover flour mixture to remove clumps.
Let cook down together for 2 minutes.
Pour over meat in crockpot.
Add tomatoes and bay leaves to crockpot.
Place lid on top of crockpot and cook on low for 6-8 hours.
The meat will be super tender. Serve over mashed potatoes or cauliflower rice.