Turn on the oven to preheat to 350 degrees. Line a sheet tray with parchment paper and set it aside. On a clean cutting board, pat chicken breasts dry with a paper towel. You may use thin-sliced chicken breasts or pound your breasts flat with a mallet to a ½” thickness. Slice the breasts into long, 2-ounce strips. Rub the olive oil into the tops of the strips and season them with salt and pepper.
In a shallow dish or on a plate, combine the everything bagel seasoning and sesame seeds into an even mixture. One by one, pick up a chicken strip, roll it in the everything sesame seasoning for 100% coverage, and lay it down on the prepared sheet tray. When all the chicken strips are prepared, bake the tray for 25 minutes, flipping the strips over about halfway through. Let the strips cool for just a few minutes after cooking.
While the chicken strips are cooling, you can make the spicy honey mustard sauce. In a small dish, whisk together spicy brown mustard and honey. In a separate dish, microwave the butter until it’s melted. Whisk the melted butter into the honey mustard. If the dipping sauce is too thick, you can microwave the completed sauce for 10-15 seconds so it’s warm and looser. Each chicken strip can have about 1 teaspoon of dipping sauce.