Fog City Diner's Tomato Ketchup

This is the house ketchup from San Francisco’s legendary Fog City Diner, and once you taste it you’ll understand why homemade ketchup became a restaurant trend in the first place. Nothing about it tastes like a commercial bottle, it’s tangier, more complex, with layered spice notes and the unmistakable flavor of fresh tomatoes instead of concentrated paste.

Using roma tomatoes is the first critical choice. Roma (plum) tomatoes have more flesh and less water than beefsteak, so they cook down into a thick, concentrated ketchup faster without hours of evaporation. Four pounds yields five cups after cooking down, so don’t skimp on quantity.

Pickling spice and a whole cinnamon stick are the flavour signatures that take this above standard homemade ketchup. Pickling spice is a mix of bay, mustard, coriander, allspice, cloves, and black pepper, it’s the secret to that unmistakable “ketchup” aroma most home recipes miss.

The two-cook technique is the professional touch. Cook, strain, then cook again. The first boil extracts and softens everything, straining removes skins and seeds, the second boil thickens the strained liquid without fibrous bits in the way. Cornstarch dissolved in cold water adds the final silky body.

Pro Tips

• Press hard on the solids when straining, the thick pulp that sticks to the underside of the sieve is pure tomato concentrate.
• Use a wooden spoon to stir, metal can react with the acid and give off-flavours during long cooking.
• Don’t over-cook after adding the cornstarch, as the recipe warns, extended cooking breaks the starch bond and the ketchup thins.
• Sterilize the storage jars for longer fridge life, a clean jar keeps ketchup fresh for the full month.

Variations

• Add a splash of bourbon or smoky whiskey in the last 5 minutes for a signature BBQ-friendly ketchup.
• Stir in 2 teaspoons smoked paprika with the spices for a smoky Spanish-style version.
• Add grated fresh ginger with the garlic for a brighter, more complex finish.
• Fire-roast the tomatoes before cooking for a deeper, slightly charred flavour.