Mince the Garlic (4 clove) and finely dice the Onion (1). Set aside.
Add Oil (2 tablespoon) to a medium saucepan on medium-high heat. Cook onions and garlic and saute until they smell sweet and look translucent, about 10 minutes.
Add Ground Cinnamon (1/2 teaspoon) and Ground Allspice (1/2 teaspoon) to the saucepan. Continue to cook with the onions for about 5 minutes, until fragrant.
Add Whole Peeled Tomatoes (1 can), Tomato Paste (3 tablespoon), Brown Sugar (1/3 cup), Apple Cider Vinegar (1/3 cup), and Worcestershire Sauce (1 tablespoon) and stir together.
Allow the mixture to come to a slow boil, then lower heat to a medium-low simmer and allow the sauce to thicken for 40 minutes, stirring occasionally.
Use an immersion blender or food processor to blend the mixture into a thick puree.
Chill for at least 1 hour before serving; the flavors will continue to develop as the ketchup cools.