Add sliced chicken and ½ cup franks red hot sauce to a bowl. Cover and place in refrigerator for 30 minutes.
Preheat grill to 400 degrees.
Now depending on the size you cut the chicken you can place it directly on the grates, in a grill basket, or on kabobs. Grill chicken for 8-10 minutes, stirring throughout.
Remove from grill and place grilled chicken in a bowl, toss with ¼ cup of buffalo sauce.
Assemble lettuce cups: place butter lettuce cups, 2-3 cubes of chicken, 2-3 diced avocado.