Heat a large, deep skillet or large saucepan over medium-high heat and add the garlic-infused oil. Once the oil is shimmering, add the ginger, fresh turmeric (if using), and cook for 2 minutes, stirring frequently to prevent burning
Add the cumin, coriander, chili powder, curry powder, garam masala, salt, and black pepper to taste, and cook for 30 to 60 seconds until fragrant, tossing frequently to prevent burning. If using ground turmeric instead of fresh turmeric, add the ground turmeric now, along with the rest of the spices.
Pour in the vegetable broth and crushed tomatoes, and use a wooden spoon or spatula to scrape up any browned bits on the bottom of the pot. Simmer for 10-15minutes, then add the canned lentils (make sure to rinse them well before adding them).
Stir in the coconut milk, peanut butter, along salt and pepper to taste Continue cooking on low heat, uncovered for 5 to 8 minutes, until the curry has thickened and is creamy.
Finally, stir in the lemon juice and cilantro, and turn off the heat. Serve the curry with rice and/or this gluten-free naan and garnish with additional cilantro. Store leftovers in the fridge for 3-4 days.