Preheat oven to 425°F (220°C). In food processor, mince together half of the onion and carrot. Dice remaining onion; set aside.
Mix together ground lamb, egg, minced vegetables, Parmesan, 1/4 cup (60 mL) parsley, half of the garlic, 1/2 tsp (2 mL) each salt and pepper and 1/4 tsp (1 mL) chili flakes. Divide mixture in half; refrigerate one half in airtight container to make koftas. Divide remaining half into 6 portions and roll into meatballs; transfer to parchment paper–lined baking sheet. Bake for 15 to 18 minutes or until golden brown and cooked through.
Meanwhile, heat oil in high-sided skillet set over medium heat. Cook diced onion, remaining garlic, chili flakes, salt and pepper for 3 to 5 minutes or until tender. Pour in tomatoes; bring to boil. Cook for 15 to 20 minutes or until thickened slightly. Add meatballs to tomato sauce; simmer for 3 to 5 minutes or until heated through.
Meanwhile, cook lasagne noodles in boiling salted water for 5 to 7 minutes or until al dente. Drain and let cool slightly. Cut each noodle in half lengthwise. Roll meatballs in halved lasagne noodles. Serve wrapped meatballs in bowls. Drizzled with remaining sauce. Garnish with crumbled feta and remaining parsley.