Combine lentils and water in a medium pot. Bring to a boil, reduce to a simmer, and cook until lentils are tender, 23 to 25 minutes. If lentils are not tender and water has been absorbed, add more water and continue to cook. Drain off any excess water.
Heat olive oil in a skillet over medium-low heat and add the red onion. Cook until onion is translucent and fragrant, 6 to 8 minutes. Stir in the garlic and carrots, cooking for another 2 to 3 minutes.
In a food processor, combine the cooked lentils, onion mixture, nuts, panko, herbs, salt, and pepper. Pulse a few times to start combining the mixture. Crack the egg in and pulse a few more times until the mixture is combined but the lentils are still holding shape. Set aside and let rest while the oven preheats to 425˚.
Combine cherry tomatoes with 2 teaspoons olive oil and chopped garlic. Place in the oven and let cook until tomatoes have released their juices and 'burst', 30 to 35 minutes. Remove from oven and set aside.
Once tomatoes are in the oven, take the lentil mixture and roll into 12 balls, roughly the size of a golfball. Place on a baking tray covered with parchment paper and brush with olive oil. Bake meatballs until browning and crisp, 25 to 30 minutes.
Cook pasta according to package and drain. When ready to assemble, combine the pasta with the burst tomatoes, meatballs, shredded cheese, and basil. Drizzle with olive oil and toss everything together to serve.
*if you would like more of a sauce than the burst tomatoes, pulse the tomatoes with a bit of olive oil, basil, and cheese before assembling.