Adobo sauce is a sauce or marinade used in Latin American- and [Southwest U.S.-style cooking, made of finely chopped or pureed chiles, garlic, vinegar, and often onions and tomatoes. Food that has been prepared with adobo is sometimes called adobado. 
Chipotles in adobo sauce is a particular use of this condiment in which chipotles (smoked jalapeño peppers) are stewed in adobo sauce. Ingredients of this sauce generally include tomatoes, garlic, vinegar, salt, and spices.
- A dozen chipotle peppers or smoked, dried jalapeño peppers (most co-ops can get these for you, or try the specialty produce section of your grocery store)
- 4 cups (.95 L) water
- ½ cup (120 mL) onion, diced
- ⅓ cup (80 mL))apple cider vinegar
- ¼ cup (60 mL) ketchup
- 3 cloves garlic, crushed or sliced
- pinch of cumin, oregano and salt to taste
Combine all ingredients in a heavy sauce pan Cook over a very low heat for 1-2 hours until the chiles are very soft and the liquid has been reduced to about 1-cup; or put in a slow cooker overnight.
Beat with a mortar and pestle or put in blender to puree for a thick sauce.
Will keep several weeks in the fridge in an airtight container, or can it in mason jars to store longer following directions for sterilizing jars and proper sealing.