Add the lentils, diced poblanos, corn, onion, and garlic to the slow cooker.
Pour in the diced tomatoes with their juice and the vegetable broth.
Stir in the cumin, chili powder, salt, and black pepper until everything is evenly mixed.
Cover and cook on low for 6 to 7 hours or on high for 3 to 4 hours, until the lentils are tender.
Taste and adjust salt or pepper if needed.
Ladle into bowls and top with fresh cilantro and a squeeze of lime.