Heat oil in a large saucepan over medium heat. Add onion; cook and stir until translucent, about 3 minutes. Mix in mushrooms, carrots, and garlic; cook until flavors combine, about 2 minutes.
Stir vegetable broth, water, lentils, quinoa, tomato paste, curry powder, chili powder, cumin, ginger, cayenne pepper, garam masala, turmeric, salt, and pepper into the saucepan. Reduce heat to medium-low and cover; let simmer until vegetables are cooked through, about 40 minutes.
Stir butter and cream into the saucepan. Replace the lid and cook until the lentils are tender, about 5 minutes.
