Rinse red and yellow lentils under cold water until the water runs clear. Add the lentils and water to an instant pot and pressure cook on high for 7 minutes, or simmer in a saucepan for 20-25 minutes until tender.

Crush cumin seeds and black peppercorns using a mortar and pestle or a spice grinder. Set aside.

In a skillet, heat oil over medium heat and add the crushed spices. Once they sizzle, add chopped onion and cook until translucent. Stir in garlic, ginger, and green chili; sauté until onions are golden brown.

Mix the sautéed onion mixture into the cooked lentils, ensuring flavors are evenly distributed. Adjust salt if needed.

In the same skillet, heat more oil and add garam masala and curry leaves. Cook until fragrant and pour this tadka over the dal, stirring well.

Garnish with chopped cilantro and lemon juice. Serve hot with rice or naan.