Preheat your oven to 400°F and line a baking sheet with parchment paper.
Slice the chicken breast into small, bite-sized pieces.
In a small dish, whisk together the first tablespoon of Greek yogurt, garlic powder, onion powder, sea salt, and black pepper.
Crush the cornflakes into a coarse meal using a sealed bag or mortar and pestle, then place them in a shallow bowl.
Thoroughly coat each chicken piece in the yogurt marinade, then roll them in the crushed cornflakes until evenly covered.
Arrange the chicken on the prepared baking sheet and bake for 12 to 15 minutes until the coating is golden and the chicken is cooked through.
While the chicken is baking, whisk the second tablespoon of Greek yogurt with the minced garlic in a small ramekin to make the garlic yogurt dip.
In a separate small ramekin, stir the yellow mustard and honey together until smooth to create the honey mustard sauce.
Serve the warm, crispy chicken nuggets immediately with both dipping sauces on the side.