Preheat oven to 375°F. Lightly spray a 9 x 11 inch baking dish with nonstick spray.
Cut the bacon slices in half and wrap each water chestnut with half a strip of bacon. Secure with tooth pick and arrange in a single layer in the baking dish. Bake for 10 to 15 minutes, or until bacon is done.
Meanwhile, combine ketchup, brown sugar, and Worcestershire in a small bowl.
Remove baking dish from oven, and pour off excess fat. Pour sauce over water chestnuts and return dish to oven. Bake for 30 minutes.
Place water chestnuts on a platter and serve immediately.
Notes
I don't recommend thick cut bacon for this recipe.
Crockpot Method: Prepare bacon wrapped water chestnuts as directed through step 3. Remove the partially baked chestnuts from the baking dish and transfer them to a crockpot, keeping them in a single layer as much as possible. Top with the sauce, cover, and cook on high for at least 30 minutes, or until sauce is heated through. Keep on warm setting and serve directly from the crock pot.