Preheat oven to 400F.
Spray a sheet pan with cooking spray and set aside.
In a large bowl, combine lemon juice, honey, soy sauce, and garlic; whisk until thoroughly combined.
Add chicken to the marinade and let sit for 15 to 30 minutes.
Place halved potatoes in a bowl and spray about 6 times with cooking spray; toss to combine.
Add garlic, and season with salt and pepper; mix and stir until combined.
Place potatoes in a single layer onto the prepared baking sheet.
Remove chicken from marinade, shake off any excess, and transfer to the baking sheet. Season with salt and pepper.
If using lemon slices, place a thin lemon slice over each chicken breast.
Bake for 30 minutes, stirring the potatoes half way through cooking.
Remove from oven.
Garnish with parsley and serve.