In a large pot on medium-high heat, add the olive oil and butter.
Add chopped onions and garlic, and sauté until the onions are translucent about 5 minutes.
Then add in the carrots and celery, and sauté for another 3 minutes.
Stir in curry powder and stir well to coat the vegetables.
Add tomatoes, stir and cook for a few minutes.
Finally add the broth, tomato paste, sugar, paprika, basil, marjoram, bay leaf, salt and pepper. Stir well and simmer for 20-25 minutes.
Remove the pot from the heat and discard the bay leaf.
Blend the mixture with an immersion blender or in batches in a high speed blender, until the mixture is smooth.
Return to the heat and simmer uncovered for 10 minutes.
Serve with a sprinkling of aleppo pepper and a side of grilled cheese.