Pea and Mint Soup

Peas cooked briefly in a potato and stock base, blended with mint and lemon and finished with buttermilk. It is a British spring soup, and no country is claimed. The short cooking is the entire technique. Peas lose their colour and their fresh sweetness rapidly once they are cooked, chlorophyll degrades with heat and acid, and the sugars that make young peas taste of anything begin converting to starch. Five minutes is what the recipe allows, and the instruction is explicit that longer will cost you the flavour. Everything else in the pot, the potato, the onions, the garlic, is cooked through first, and the peas go in at the very end. The potato is doing structural work. It breaks down under the blender and thickens the soup, which is why no flour or cream is needed for body. Buttermilk rather than cream is the other choice worth noting. It brings richness with acidity behind it, which lifts the whole thing where cream would flatten it. The trade-off is that it curdles at a rolling heat, so the soup must be warmed through gently. It works hot or cold. Served cold it will thicken as it chills and needs loosening with more stock.