Using a mallet, flatten each chicken fillet to about 1/3” thickness.

Place pecans, panko, orange zest, chipotle, and salt & pepper in a food processor, and pulse until the pecans are crumbled well and the mixture is uniformly breadcrumb-like. Pour into a shallow dish.

Dip each piece of chicken into the egg whites, gently shake off the excess, and then dredge in the pecan breadcrumb mixture. Coat well.

Spray a large, nonstick skillet with an olive oil mister or cooking spray, and set over medium-high heat. Add the chicken, cover, and cook until browned on the outside and no longer pink in the middle, about 3-4 minutes per side. Serve immediately.