Make the honey mustard: In a bowl, whisk together the Dijon, whole grain mustard, honey, apple cider vinegar, 1 tablespoon of the olive oil, and the garlic. Set aside about half the sauce for drizzling and use the rest to coat the chicken.

Marinate the chicken: Season the chicken with 1/2 teaspoon of the salt and the pepper, then toss it with the reserved marinade portion. Let it sit while the oven heats, or up to overnight in the fridge for deeper flavor.

Roast the vegetables: Preheat the oven to 425°F. Toss the broccoli with the remaining 1 tablespoon olive oil and 1/4 teaspoon salt, spread on a sheet pan, and roast for 18-20 minutes until the edges are browned and crisp.

Sear the chicken: While the vegetables roast, heat a skillet over medium-high heat. Cook the chicken for 5-7 minutes per side, depending on thickness, until browned and cooked through to 165°F on a meat thermometer. Let it rest 5 minutes, then slice.

Build the bowls: Divide the rice among four bowls and top with sliced chicken and roasted broccoli. Drizzle with the reserved honey mustard sauce and scatter parsley over the top.