1. Grab some ingredients you like. Red paprika or bell pepper works, tomatoes are a classic, and don't shy away from fruits like grapes, lemons, or oranges. I recommend any combination of the first three for a base, and a little bit of some random fruit to add a little special kick that you only get from home made ketchup. Also, smaller tomatoes usually have more flavour than large ones.
2. Grab the defining ingredients of ketchup. That's onions and vinegar. Use whatever vinegar you like. I use some kind of grape-based vinegar because it's what I have at home.
3. Grab whatever you wanna use for seasoning. You definitely need salt. I think you're supposed to use garlic, but I have made it without garlic before and it turned out fine, but garlic is good. Curry works great, as do spicy chili peppers, dried or fresh, doesn't matter. Alternatively you can use whatever you have in the kitchen that seems like it would taste good in ketchup, or you can look up what the normal seasonings tend to be. Keep in mind that curry isn't part of the standard ketchup recipe, so if you use it, you're making curry ketchup.
4. Toss the onions into your pot with some kinda oil or butter or whatever, and fry the everliving fuck out of them until they caramelize. Don't use too much heat or they'll burn.
5. Just as the onions get dangerously close to getting burnt, douse them with the fruits, tomatoes, bell peppers, or whatever the fuck else you decided to use as your main ingredient mix.
6. Boil the shit out of your proto-ketchup. If there's too little liquid, add a little bit of water. Your main ingredient mix should usually contain enough liquid to facilitate boiling, though. Especially if you used tomatoes. Do not add water if you used a lot of tomatoes! The tomatoes will bleed enough liquid, trust me. While boiling, the ingredients should turn to mush. Boil them for a long-ass time (like thirty minutes or whatever) at a low setting to really fucking disintegrate them. Stir occasionally, to make sure nothing gets burnt and stock to the pot.
7. Turn up the heat and a stir A LOT. You're "reducing" your mixture, to remove excess liquid. Really concentrate that shit into a thick paste. Not too thick, though. Just enough that the mixture doesn't bleed a large amount of liquid while stirring. If it burns, you reduced it too much. Consider opening a window or something, because you're turning a lot of water into steam, so it's gonna get humid as fuck.
8. Blend that shit. Blend the fuck out of it. Blend it nice and fine and smooth! If you're really picky about how smooth your want your ketchup, you can use like a fine sieve and press it through that with a spoon or something, but that's a lot of work and I don't think it's worth it. I recommend you don't bother, it'll still be good without that extra step.
9. If you took the ketchup out of the pot to blend it, you might want to put it into a fresh pot, but it's up to you whether you think that's worth it. Either way it needs to go back into the pot now, if it isn't there already. It's time to season that shit! Add whatever amount of vinegar you think is right (if you used especially sour main ingredients, you might not even need any vinegar), salt it, and add whatever herbs or spices you want in there. You know, the ones you prepared in step 3. Try your mixture and see if it still needs anything. If it's too thick, add a little water until it has the desired consistency. If it's too thin, make sure to put a lid on your pot while you reduce it again, because once that shit is blended, it spits like a fucking lava pool. If you really, absolutely, definitely think it's not sweet enough, you can add some sugar. But the red peppers and/or fruits you probably used should have enough sugar, usually.
10. Once it tastes right, carefully boil it again to make sure no bacteria have survived in there. Again, it's going to spit like a motherfucker, so use a fucking lid to avoid burns and a huge fucking mess all over your fucking kitchen.
11. While it's still boiling hot (but not actually literally boiling any more because that shit spits like a bitch), carefully put it into whatever container(s) you want. I recommend empty jam jars made of glass, that have been cleaned out, because they come for free when buying jam. Mason jars work, too. Also there's like specialized squeeze bottles you can buy? Whatever works best for you.
12. Let it cool a bit in its sealed container, then when it's cool enough, put it in your fridge. The next day, your ketchup is ready to use!
13. Use it for whatever the fuck you like to use ketchup for.
Bone apple tea.
You may have noticed I didn't give you any amounts or ratios. That's because I never measured any of this shit out with any degree of precision. Figure it out yourself! Everyone's taste buds are different and you can use whatever tastes best to you. There are a ton of precise recipes that tell you EXACTLY what to use, but where's the fun in that? Just improvise! Or use another recipe if you're THAT afraid of getting it wrong.
Make small batches at first, to learn how to get it right, and so you don't have too much of a ketchup you don't like in case it doesn't turn out right. Once you're confident you can make good ketchup, you can start making larger batches, assuming you even eat enough ketchup to justify large batches to begin with.
Why am I writing this shit down? Because commercial ketchup is a fucking candy syrup that tastes so sweet that I would rather pour it on ice cream than on any kind of meat-based food product. And also because I fucking felt like it.
If you disagree with any part of this recipe, then adapt it to your tastes, or ignore it entirely. I'm not your fucking parent, do whatever the fuck you want. I can't stop you.
