This red lentil soup simmers lentils with fire-roasted tomatoes, cumin, turmeric, fresh ginger and plenty of garlic until they break down, thick and hearty. Stir in spinach and lemon at the end for 21 grams of plant protein per bowl, no soaking required.
Heat the avocado oil in a large pot over medium-high heat. Add the onion and celery and sauté until the onion is translucent, about 5 minutes.
Add the garlic and ginger and cook, stirring constantly, for 1 minute. Add the cumin and turmeric and stir until fragrant, about 30 seconds, then stir in the tomatoes.
Add the vegetable stock and lentils and bring to a simmer. Reduce the heat, partially cover and cook until the lentils are soft, 25 to 30 minutes.
Stir in the spinach and lemon juice and season to taste with salt and pepper.
Serve topped with the cilantro, avocado and red pepper flakes.
Notes
Slow Cooker Method: Add everything except the spinach and lemon juice and cook on low for 6 hours or high for 2 1/2 hours, checking early so the lentils don't turn mushy. Stir in the spinach and lemon juice at the end.
Ingredient Swaps: Use 1/4 teaspoon ground ginger in place of fresh. Fresh turmeric root also works in place of ground; use about 1 tablespoon grated.
Spice Level: For a milder soup, leave out the red pepper flakes and use regular diced tomatoes.
Storing: Leftovers keep in the fridge for up to 5 days or the freezer for up to 3 months. The soup thickens as it sits, so thin it with a splash of stock when reheating.