In a bowl, whisk mustard, shallot, honey, olive oil, rosemary, lemon juice, salt, and pepper. Set aside half of the mixture in the fridge for serving later.

In a Ziploc bag or bowl, mix chicken with the remaining marinade. Refrigerate for at least 2 hours (or up to 8 hours), turning occasionally.

Preheat grill to medium heat.

Brush chicken with canola oil, season with salt and pepper. Grill for 8 minutes, turning occasionally, until fully cooked (165°F).

Brush with reserved marinade and grill for another 1–2 minutes.

Serve warm and enjoy every bite!