PREP: Measure the lentils and pick over to remove debris or shriveled lentils, and then thoroughly rinse with water. Add them to a bowl, cover them in room-temperature water and let soak for 15-20 minutes. Prep the veggie:; finely dice the onion and carrot; finely mince the garlic cloves and finely mince the ginger.
SAUTE: Add the 3 tablespoons butter or oil to a large pot. Heat to medium and once the butter is melted or oil is shimmering, add in the 1 cup onion, 1 tablespoon garlic, and 1 and 1/2 tablespoon ginger. Cook and stir for 3-4 minutes. Add in the 1 cup diced carrot. Cook, stirring occasionally for another 6-8 minutes or until everything is golden. Nothing should be overly browning or burning; if so, turn down the heat. While everything is cooking, measure out the spices.
SPICES AND TOMATOES: Add the 2 tablespoons red curry paste, 1 tablespoon yellow curry powder, 1 and 1/2 teaspoon garam masala, 1 and 1/2 teaspoon paprika, 1 and 1/2 teaspoon ground coriander, 1 teaspoon cumin, and 3/4 teaspoon turmeric. Season with salt and pepper; I add 1 and 1/4 teaspoon fine sea salt and 1/2 teaspoon ground pepper. Increase the heat to high, and stirring constantly, cook for 1-2 minutes or until very fragrant. Add in the tomatoes and reduce the heat to medium. Stir and cook for 1 minute, scraping the bottom of the pot to release any browned bits. Add in 1 teaspoon sugar.
LENTILS AND LIQUIDS: Thoroughly drain the lentils. Add to the pot along with the can of coconut milk and 3 cups chicken or vegetable broth/stock. Bring to a boil and then reduce to a gentle simmer. Cover with a lid and cook for 30 minutes, stirring every 8-10 minutes. Remove the lid and simmer for another 5-8 minutes or until curry is thick and creamy and lentils are completely tender. If the mixture thickens too much, add a splash of broth or stock and if it's too thin (or lentils aren't tender), increase the heat a bit and simmer without the lid.
FINISHING: Add in the 1/3 cup finely chopped cilantro and if desired, stir in the zest and juice of a lemon. Taste and adjust any seasonings; flavors should sing, so add extra salt,pepper or lemon juice if needed. Serve over cooked basmati rice if desired (Note 2) and enjoy hot.