Heat oil in a large pan over medium-high heat. Add the ground beef and cook for 5-7 minutes, breaking it apart as it cooks, until fully cooked (internal temperature 71°C/160°F). Add the chopped onion and garlic, cook for 1-2 minutes until softened. Add the tomato paste and cook for 2 minutes. Add sambal oelek if desired. Season with curry powder and cook for 1 minute.
Cut the bell peppers into cubes and cut the spring onions into rings. Add them to the pan and cook for 2-3 minutes. Pour in approximately 500-700 ml vegetable stock. Reduce heat to medium and simmer for 5 minutes until the vegetables are tender-crisp. Season with hot paprika powder, sweet paprika powder, salt, and pepper. Add a small amount of sugar if needed to neutralize acidity. If the sauce is too thin, stir in a little flour to thicken.
Divide the cooked pasta among plates and pour the sauce over top.
Optional: For a lighter version, use 150-200 g ground beef and add grated carrots to fill the volume, adding the carrots with the peppers and spring onions in step 3.