Add the dried lentils to 1½ cups of water in a sauce pan and bring to boil. Cover the lentils with a tight fitting lid and reduce to simmer. Simmer for 15-20 minutes until the liquid is absorbed and the lentils are soft. Any remaining liquid can be drained off.
While the lentils are cooking, remove the mushroom stems and slice the mushrooms. Remove the papery layer of the onion and dice the onion into ¼-inch pieces.
Add the mushrooms and onion to a skillet and sauté until the mushrooms are soft and the onion is translucent.
Cut off the ends of the garlic clove and press the clove under the flat side of a knife to remove the papery layer. Mince the garlic and add it to the skillet.
Add the spices to the skillet and stir to combine. Cook until the garlic is fragrant.
When the lentils and mushrooms are soft, add the lentils, mushroom mixture, and flour to a food processor.
Pulse the food processor until the mixture is soft and fully incorporated.
Remove the dough and roll into 12 equal balls (about 1/2 inch across). Slightly dampen your hands to prevent the mixture from sticking. Place the balls on a baking sheet and bake for 20 minutes.
Notes
Reheat the meatballs in a skillet with your sauce of choice. Check out my basic marinara recipe to go enjoy these meatballs with.