For the pea soup
Bring a pot of salted water to the boil and cook peas (adding enough so as not to stop the boiling process. If necessary repeat the process). Cool the peas in iced water and strain. If the peas are frozen, this step can by skipped by increasing the cooking time for the peas in the following stage. Place a pot over medium heat and add the butter and olive oil. Add onion, season with salt and sweat until completely soft. Add the rosemary and garlic and once they release their aroma, add the stock. Bring to the boil, season with salt and cook for about 10 minutes. Add the peas and continue to boil for 1-2 minutes. Remove from the heat, blend and pass through a fine sieve. Taste and season if necessary.
If not planning to serve immediately, place the soup in a bowl inside a bain-marie on ice, so that the soup cools rapidly and maintains its colour.
For the bruschetta
Drizzle the olive oil over the bread slices and season with salt. Place in a baking dish lined with parchment paper and cook in a preheated oven at 180°C until completely dry. Heat a frying pan on a medium to high heat, add 10 gr. olive oil and sauté the sausage until crisp. Remove onto absorbent paper.