Step 1
Place all ingredients in a medium pot, whisk to combine.
Step 2
Over medium low heat, bring the mixture to a gentle simmer.
Step 3
Cook, stirring and scraping the pot occasionally, for about 10 minutes. The mixture will be thickened, and should measure to be about 1 cup.
Step 4
Place ketchup in a fine mesh strainer set over a bowl. Press on the solids to get as much ketchup as possible.
Step 5
Discard the solids from the strainer. Let the ketchup cool, then keep ketchup refrigerated in an airtight container.
