"Maple's" Roasted Potatoes

I tweaked this recipe from a cookbook called "Vegan with a Vengeance". It is the best side dish, without a doubt.
Ingredients (makes 6-8 portions):
2 pounds of potatoes cut into 1 inch pieces
a pinch of salt and pepper
½ pound of string beans, ends cut off (I have also used carrots)
1 yellow onion, sliced (optional)
2 cloves of garlic, minced
3 tablespoons of soy sauce
1/2 cup of maple syrup (real is best)
3 tablespoons of mustard (I use dijon)
2 tablespoons olive oil

1) Preheat oven to 400. Place veggies in 9 x 13 casserole dish. In a mixing bowl stir all other ingredients. Pour over veggies and mix until evenly coated.
2) Cover with foil and bake in oven for 25 minutes. Take out and stir veggies, ensuring sauce is distributed evenly on veggies. Turn oven down to 350 and cook for an additional 25 minutes, uncovered.
3) Remove from oven, toss again. Bake for a final 25 minutes. Let sit for 5 minutes. Enjoy!