Begin by cooking the bacon slices about halfway, using your preferred method (such as frying in a skillet or baking). Once the bacon is partially cooked, transfer it to a paper towel to drain excess fat. Allow the bacon to cool slightly, then chop it into semi-bite-sized pieces. I find chopping the bacon after it cools gives a cleaner cut and less mess.

Preheat your oven to 325°F (163°C) and set the rack to the lower-middle position to ensure even heat distribution during baking. Meanwhile, lightly grease a 13x9-inch baking dish or another 3-quart oven-safe vessel to prevent the beans from sticking.

In a deep skillet over medium heat, add about 2 tablespoons of the reserved bacon grease from Step 1 (or substitute with butter if preferred). Add the finely chopped yellow onion and diced green bell pepper to the skillet. Sauté for about 5 minutes, stirring occasionally, until the vegetables are softened and fragrant.

To the softened vegetables in the skillet, add the canned pork and beans (with all their liquid), ketchup, molasses, packed brown sugar, apple cider vinegar, and ground dry mustard. Stir everything together thoroughly and let the mixture simmer gently for about a minute to meld the flavors. I like to taste the sauce here and adjust with a bit more vinegar or sugar if I want it tangier or sweeter.

Pour the simmered bean mixture from Step 4 into the greased baking dish prepared in Step 2. Evenly distribute the chopped, partially cooked bacon from Step 1 over the top of the beans.

Place the baking dish in the oven and bake uncovered for 2-3 hours, depending on your preference for consistency. The longer bake time will yield thicker beans. I like to check after 2 hours and give the beans a gentle stir to see if they're as thick as I like.

Remove the baked beans from the oven and let them stand for about 5 minutes before serving. This resting time helps the sauce thicken and makes serving easier. Enjoy your homemade baked beans!