Heat 1 tbsp olive oil in a deep pan over medium heat.
Add the onion and shallot and sauté until soft.
Add the garlic and cook for another 1-2 minutes.
Pour in the white wine, bring to a boil, and let it reduce for a few minutes.
Stir in the chopped tomatoes, tomato purée, and sugar.
Season with salt and pepper.
Simmer uncovered for 20-25 minutes until the sauce thickens.
If necessary, remove the membrane from the monkfish.
Rinse, pat dry, and cut into 2.5 cm chunks.
On a plate, mix the flour with salt and pepper.
Lightly coat the monkfish in the flour, shaking off any excess.
Heat 2 tbsp oil and butter in a frying pan over medium heat.
Cook the monkfish for about 3 minutes per side until golden brown.
Let it rest for a few minutes.
Spoon the tomato mixture onto plates and place the monkfish on top.
Garnish with chopped parsley and serve immediately.
Notes / Tips / Wine Advice:
Serving Tip:Serve with crusty bread or a side of steamed vegetables for a complete meal.Wine Advice:Pair with a crisp Sauvignon Blanc or a light Chardonnay to complement the delicate flavors of the monkfish.