1. Wash the leeks and finely chop them. Peel the onion and slice it.
2. In a sauté pan, heat a little olive oil. Add the leeks and onion, sauté them over medium heat for 2 minutes.
3. Deglaze the mixture with white wine and let it reduce. Then cover with boiling water (and a bouillon cube if desired). Simmer over low heat for about 20 minutes. Stir regularly until the leeks are tender and the water has evaporated.
4. In a bowl, beat the eggs, add the cream, milk, flour, grated or diced cheese, salt, pepper, curry, and drained leeks. Mix to obtain a homogeneous mixture.
5. Line the bottom of tartlet molds with parchment paper, as shown here, or use a cake or tart pan. Pour the mixture into it, spreading it evenly. Finally, bake at 200°C for about 25 to 30 minutes, depending on the size of your dish.