Finely chop the onion, mince the garlic and dice the carrots into small pieces.
Heat the olive oil in a large saucepan over medium heat. Add the onion and cook for 3–4 minutes until softened. Stir in the garlic and cook for another 30 seconds.
Stir in the diced carrots and cook for 1–2 minutes, allowing the ingredients to absorb the flavours.
Add the chopped tomatoes, dried mixed herbs, oregano and stock. Stir well and bring to a gentle boil. Reduce the heat, cover partially and simmer for 20–25 minutes, stirring occasionally, until the lentils are soft and the carrots are tender. Add a little extra water if the sauce becomes too thick.
Add the lentils for the last 5 minutes to warm through .Season with black pepper and salt if needed.
Arrange the meatballs in a single layer in the air-fryer basket. Cook according to the packet instructions, usually at 180°C for approximately 10–15 minutes, turning halfway through. Ensure they are thoroughly cooked in the centre, following the package guidance.
Meanwhile, cook the pasta in a saucepan of salted boiling water according to the packet instructions. Drain, reserving a little pasta water.
Stir the cooked pasta into the lentil and vegetable sauce. Add a splash of reserved pasta water if needed to loosen the consistency.
Divide the pasta between bowls and top with the air-fried meatballs. Finish with a little extra black pepper or fresh herbs if desired.