Buttered Pear, Brie and Manchego Toastie with Onion Crème Fraîche Recipe

Name: Buttered Pear, Brie and Manchego Toastie with Onion Crème Fraîche Recipe
Cuisine: European, British, Mediterranean, French
Ingredients: 1 tsp butter; 1 sprig of rosemary; 2 pears, firm, sliced into wedges; For the walnut butter; 50g of walnuts, toasted; 1 tbsp of butter; 1 pinch of salt; oil, for frying; 1 onion, thinly sliced; 1 tsp sugar; 1 tbsp of Calvados, or white wine; 100ml of crème fraîche; salt to season; 1 handful of radicchio; 1 handful of chicory leaves; 1 tbsp of pickled walnuts, chopped; olive oil, to dress; sherry vinegar, to dress; salt and pepper to season; 4 slices of rye bread, or walnut bread; chilli jam, as needed; 100g of brie, sliced; 50g of manchego cheese, grated; mayonnaise, as needed; butter, for frying