Sweet Potato-and-Red Lentil Curry

INGREDIENTS

4 cups

peeled, cubed sweet potato (about 2 medium)

3 1/2 cups

water, divided

2 cups

dried red lentils

2 cups

low-sodium fat-free vegetable broth

3/4 cup

finely chopped white onion

3 tbsp

Thai red curry paste (such as Thai Kitchen)

2 tsp

garam masala

2 tsp

grated peeled fresh ginger

2 tsp

ground turmeric

Cooking spray

1 tbsp

sugar, divided

3/4 tsp

kosher salt

garlic cloves, minced

1 6 ounce can

tomato paste

1 cup

canned light coconut milk

1/2 cup

apple cider vinegar

1 cup

very thinly sliced red onion

4 cups

hot cooked brown rice

1 cup

fresh cilantro leaves