Heat a large frying pan over a high heat. When hot, melt 15g of butter and toast the walnuts, stirring often, until they turn a nice golden colour. Transfer to a plate and set aside.
Return the pan to the heat and heat the oil and 15g of butter. When the mixture becomes slightly frothy, add the diced pumpkin and fry for about 5 minutes, stirring regularly, until the pumpkin is cooked and lightly browned. Sprinkle with rosemary and season with salt and pepper.
Fry the pears cut into quarters quickly with 15g of butter until they are brown.
Preheat the oven to 220°C. Drizzle the bread slices with olive oil and place them in the oven to toast for a few moments, about 5-8 minutes.
Remove the sandwiches from the oven and top them with the pumpkin, pear, Roquefort and honey. Place in the oven for a few more minutes, until the cheese begins to melt.
Add the nuts, some herbs, adjust the seasoning and serve immediately.