Kansas City barbecue sauce

Units

Temperature

Servings

Ingredients

500 g ketchup, the base; a plain one, not a reduced-sugar one, which will not behave
120 ml cider vinegar
80 g molasses, the colour and the bitter edge underneath the sweetness
60 g dark brown sugar
60 ml water
30 g tomato paste, for depth the ketchup alone does not have
30 ml Worcestershire sauce, see the notes if this needs to be vegetarian
20 g yellow mustard
8 g smoked paprika
6 g garlic granules
6 g onion granules
6 g fine salt
4 g coarse black pepper
2 g cayenne, not for heat so much as to stop the sweetness sitting flat

Whisk everything together cold in the pan before any heat goes under it. Tomato paste and mustard will not disperse once the sauce is hot and you will be chasing lumps.
Bring it to a bare simmer, then turn it as low as it will go. It should barely move.
Cook 30 minutes uncovered, stirring every few minutes and scraping the bottom properly. This sauce catches and burns more readily than anything else on the stove, because it is mostly sugar in a thin layer.
Taste at the end, not the start. Raw it is aggressively sweet and sharp at once; thirty minutes turns it into one thing.

It is a finishing sauce, not a marinade. Sugar starts to burn around 160°C. Brush it on in the last 20 minutes of a cook, or after the meat comes off. Put it on at the start and you get a black bitter shell over raw-tasting meat.
Two coats beat one thick one. Brush, let it set for 10 minutes in the heat, brush again. A single heavy coat slides off and pools in the tray.
The molasses is doing more than sweetening. It brings a bitterness that stops the sauce being one-note, which is exactly what most bottled versions are missing. Do not swap all of it for more brown sugar.
It keeps a month in a clean jar in the fridge. The vinegar and sugar do the preserving.
If it is too thick the next day, which it will be, loosen it with a spoon of water or cider vinegar rather than reheating it.

Worcestershire sauce contains anchovy in every standard bottle, so this is not vegetarian as written. For a vegetarian version use a tablespoon of soy sauce plus a teaspoon of white miso, which covers the same savoury ground. Most Worcestershire is also made with malt vinegar and so is not gluten-free; the soy and miso route needs tamari to stay gluten-free.
Molasses is sold in Germany as Zuckerrübensirup, which is beet rather than cane and slightly less bitter. It works. Black treacle is closer still. Do not use blackstrap, which is genuinely bitter rather than pleasantly so.
Ketchup is the shortcut the style is actually built on, so there is no purism to defend here. If you want to start from passata instead, use 400 g of passata plus 60 g of sugar and expect to cook it twice as long.