Austro-Hungarian Cream of Horseradish Soup

Ingredients

• 1 lb potatoes (high-starch, like russets)
• 2 medium onions
• 1.5 oz butter
• 2 cup vegetable stock
• 1 cup chicken stock
• 1 cup heavy whipping cream
• 1 large egg yolk
• 2 tbsp dry white wine
• 1.5 oz horseradish, freshly grated
• black pepper
• salt
• fresh dill, chopped
• good quality olive oil

Method

Melt the butter in a heavy-bottomed pot over medium heat. Once foaming, add the diced potatoes and onions — aim for roughly 1 cm pieces so they cook at the same rate. Cook for 5–7 minutes, stirring occasionally, until the onions turn translucent and the potato surfaces begin to soften but show no colour. This initial aromatic-vegetables stage builds flavour without browning, which would darken the soup and muddy the clean horseradish bite you're after.

Pour in both stocks and bring to a rolling boil uncovered. Once boiling, reduce the heat to a steady simmer — not a whisper, but a gentle, consistent bubble — and cook for 15–18 minutes until the potatoes collapse easily under a spoon. The starches from the russets will begin to leach into the liquid, which does the thickening work for you. Pureeing the soup now with an immersion blender creates a smooth, cohesive base; work the blender in slow, deliberate strokes to avoid incorporating too much air, which would make the final texture foamy rather than velvety.

Return the pot to medium-high heat and stir in the cream. This is where precision matters: you want the soup to reach a bare simmer — small, lazy bubbles breaking the surface — then stop. Remove from heat immediately. Tempering-eggs prevents the yolk from scrambling: whisk it together with the white wine in a small bowl, then ladle in three additions of the hot soup while whisking constantly. Pour this mixture back into the pot in a thin stream, whisking the whole time. The residual heat thickens the yolk slightly, binding the cream and stock into a silken emulsion. If you've done it right, you'll feel a subtle resistance as you whisk — the soup has gained body without any obvious thickening agent.

Fold in the freshly grated horseradish — its pungent volatile oils will be strongest raw, so add it off the heat. Taste and season with salt and black pepper. Serve in warm bowls, each one finished with a scattering of chopped fresh dill and a thread of good olive oil. The dill and oil add brightness and richness; together they cut the richness of the cream and keep the horseradish's heat from becoming one-note.