Vegetarian eating doesn't have to be short on flavor, and these burgers are the proof in the pudding. They use cooked sweet potato as a binder, so plan them for the day after you're making sweet potato and cook an extra so you can use leftovers to save time.
2 Tbsp. olive oil, divided
1/2 onion, finely chopped
1 beet, finely diced
3 garlic cloves, minced
1 (15 oz.) can black beans, rinsed and drained
1/2 cup whole wheat bread crumbs
1/4 cup whole wheat flour
2 Tbsp. minced fresh parsley
1/2 tsp. salt
1/2 tsp. pepper
1/2 tsp. thyme
1/2 tsp. coriander
1/2 cup cooked sweet potato
7 oz. sharp cheddar, grated, divided
Juice of 1/2 lemon