Mix 1 Tbsp tomato paste (or ketchup but be aware of the added sugar), 1 Tbsp cider vinegar, 1 tsp chipotle powder (or smoked paprika/cayenne mix), ½ tsp cumin, a pinch of oregano, a pinch of garlic powder, and a pinch of salt (source: https://www.pepperscale.com/chipotle-in-adobo-sasuce-substitute/).
