Sauté the onion: Heat the oil in a pan over medium heat. Add the diced onions and cook until translucent.
Add the aromatics: Add minced garlic, grated ginger, and red chili flakes. Cook for about 30 seconds until fragrant.
Add seasonings: Stir in diced tomatoes, turmeric, paprika, thyme, bouillon powder, salt, and pepper. Cook for 2-3 minutes.
Stir in potatoes and carrots: Add the potatoes and carrots to the pan. Add water, stir gently, cover, and simmer on medium heat until tender (about 15-20 minutes).
Add cooked meatballs and diced bell peppers to the pan. Simmer uncovered for an additional 3-5 minutes.
Add the thickener: Mix tapioca or all-purpose flour with water and stir into the sauce until thickened.
Adjust the seasoning and garnish: Taste and adjust seasoning as needed. Garnish with fresh herbs if desired.
Serve hot.