Preheat the oven to 400˚ F (205˚ C). Top and tail the onion. Peel, then slice thinly perpendicular to the cut ends.
While you're slicing the onion, put a large frying pan on medium-low and add the bacon fat and butter/olive oil. It will melt pretty quickly, so keep an eye on it. Dice the guajillo chili pepper and reserve 1/2 of the seeds; add these to the pan.
Once the fats have infused with the pepper, add the garlic and onions. Let the onions sweat, then start to cook down, about 35 minutes if you have the time. If you don't, sauté them for about 10 minutes and then sprinkle the 1/8 teaspoon of baking soda over the onions and stir well, letting them cook down for another 5 minutes. They won't be properly caramelized, but they'll still add fantastic flavor.
Put the water on to boil the pasta. Add the ground meat to the onions, seasoning with salt, pepper, paprika, oregano, and Tabasco to taste. Turn the pan up to medium-high and cover, stirring occasionally to break up the meat until it's cooked through (about 12 minutes).
Cook the pasta, and add the pasta sauce into the pan with the meat and onions. Turn the heat on the pan down to low and stir.
Drain the pasta and dump into a lightly-oiled baking dish. Pour the sauce mixture on top and stir until well combined. Add in dollops of the ricotta and mix intermittently (I like my pasta bakes to be uniformly mixed -- if I wanted layers I'd make a lasagna!).
Sprinkle the mozzarella thickly on top, cover with aluminum foil, and bake for 45 minutes. For a crispy top, remove the foil and bake for an additional 15 minutes. Serve piping hot with a vinegary green salad!