Preheat oven to 400 and prepare a large rimmed jelly roll pan with parchment or silpat mat.
In medium sized saucepan, saute onion and garlic for 3 - 5 minutes (add a small bit of water to prevent burning)
Add rinsed red lentils and diced sweet potato. Cover all ingredients with 1 cup water and bring to boil. Simmer for 15 - 20 minutes until potatoes are soft. Drain well.
Place potato mixture in bowl and mash with fork or potato masher. These do not need to be pureed but most big chunks should be 'mashed' consistency.
Add to potato mixture cumin, coriander, salt and minced cilantro (optional)
Shape potato mixture into small oblong croquette shape (about 1 - 1 /2 inches long).
Place gluten free breadcrumbs in small shallow dish.
Roll each croquette in the breadcrumb mixture. Place on prepared baking pan.
Bake in oven for 25-30 minutes, flipping the croquettes halfway through baking time.
Store leftovers in the fridge in a covered container for up 3 - 5 days.