In a bowl, whisk together Dijon mustard, honey, olive oil, vinegar/lemon juice, garlic, salt, and pepper.

Add chicken tenders to a zip-top bag or bowl and pour marinade over. Let sit for at least 30 minutes (up to overnight in the fridge).

Preheat grill to medium heat. Oil the grates lightly.

Grill chicken for 4–5 minutes per side, or until fully cooked and lightly charred.

Let rest a few minutes before serving. Brush with a little extra marinade (that hasn’t touched raw chicken) for extra flavor.