Heat a dutch pan over medium heat. Add the oil and gluten free starch or flour. Stir or whisk together until a roux is formed. Around 10 minutes to 15 minutes. Be sure not to let it burn. It should turn a light brown caramel color.
Next add your onions, celery, bell pepper, and garlic. Sauté until fragrant, about another 5 minutes, whisking frequently. Add the remaining ingredients, minus the tomato sauce and salt/pepper.
Bring to a quick boil then reduce to low and simmer for 20 minutes or until lentils are cooked through.
Add your tomato sauce the Last 5 minutes of cooking, stir together and keep warm. Season with kosher/salt and pepper to taste. Adding too much salt to lentils while cooking can ruin texture, so adjust salt content after cooked.
Serve into bowls and garnish with jalapeño and cilantro. *Optional* Since the cauliflower rice is added to the pot to thicken, you don't need to serve this over rice, but you can and it's just as tasty! Or serve over additional cauliflower rice (cooked) to keep it light.