Duck Bolognese

Name: Duck Bolognese
Ingredients: 300 grams duck meat (aiguilettes de canard or 1 duck thigh); 300 grams ground beef; 6-8 medium tomatoes; 2-3 finely chopped shallots; 2 finely chopped garlic cloves; 1 bay leaf; 1 handful fresh thyme, rosemary and/or oregano; 100 milliliters approx. of red wine (1 small glass); 100 grams chopped chicken liver; a few tbsp olive oil; 1 teaspoon butter + a pinch of flour to drench the liver; fine salt/fleur de sel + freshly ground pepper to taste