Maple-Mustard-Glazed Potatoes and String Beans

2 lbs. small yukon gold potatoes, halved (about 1 inch pieces)
1/2 lb. string beans, halved, ends cut off
1 yellow onion, thickly sliced
2 cloves garlic, minced
3 Tbsps. tamari or soy sauce
1/4 cup maple syrup (agave or honey is a good sub.)
3 Tbsp. Dijon mustard
2 Tbsp. Olive oil

Preheat oven to 400.
Place the vegetables in a 9x13 inch casserole dish.
In a mixing bowl, stir together all the other ingredients until the mustard is dissolved. Pour over the vegetables and mix well until everything is coated. Cover with foil and place in oven. (I use a cookie sheet over top of pan instead of foil). Bake for 25 minutes. Remove from oven and toss everything; use a spoon to drip the sauce over the veggies. Turn oven down to 350, and cook for 25 minutes uncovered. Remove from oven, toss again, cook for 25 more minutes uncovered. These are especially yummy served at room temperature, with some of the sauce remaining poured over them.