Place chipotle peppers in a food processor or blender and puree.

In medium bowl add ground beef, pureed peppers, lime juice, onion powder, garlic powder, salt and pepper. Mix until completely combined.

Form 4 burger patties, and grill to temperature of your liking. At the same time toast the burger buns.

While burgers are grilling, slice onions.

In Skillet or pan melt butter, place onions in pan and allow to caramelize about 8-10 minutes over a medium high heat.

To assemble, on bottom bun lay lettuce, then burger patty, then about 1 Tbsp. of Adobo Sauce, top with onions. Close up and enjoy!