Chipotle Mayo Burgers with Grilled Onions

Not sure if you noticed, but lately the Giles' have been digging their chipotle chilies in adobo sauce. I'm pretty sure that I've raved about it before on the Blog, but if not, here I go again. If you make any of your own 'tex-mex' type food (tacos, fajitahs etc.), chipotle chilies in adobo is a MUST. Tonight I decided to mix it into some mayonnaise and serve up my burgers with some nicely grilled red onions. It's fun to spice up an old classic. Also had some nice fresh Canadian feta in the fridge, so I threw some of that on for good measure too. YUM. Burgerlishious. Bon appétit!

Ingredients
1 1/4 pounds ground chuck
kosher salt and black pepper
canola oil, for the grill
1 medium red onion, cut into four 1/2-inch-thick slices
1/2 cup mayonnaise
1 to 2 tablespoons chopped chipotles in adobo sauce
2 teaspoons lime juice
4 buns (we make ours fresh from our homemade pizza dough recipe!)
1/2 cup fresh cilantro leaves

Directions
1. Heat grill to medium-high. Form the beef into four ¾-inch-thick patties. Use your fingers to make a shallow well in the top of each patty. (This will prevent overplumping during cooking.) Season with a total of ½ teaspoon each salt and pepper.

2. Oil the grill and cook the patties with the wells facing up for 4 to 5 minutes. Flip and cook 4 to 5 minutes more. Grill the red onion until tender, 4 to 5 minutes per side.

5. In a small bowl, combine the mayonnaise, chipotles, and lime juice. Dividing evenly, spread the buns with the mayonnaise mixture. Form burgers with the mayo, burgers, onions, and cilantro.