Equipment
Ingredients
Base
- 250 g unsalted butter, cut into cubes
- 200 g lobster shells, crushed into small pieces
- 50 ml water
Aromatics & Seasoning
- 15 g tomato paste
- 15 ml cognac
- 2 g sea salt, fine
Nutrition (per serving)
Method
Preheat the oven to 200°C/400°F. Spread the crushed lobster shells evenly in a single layer on a baking sheet.
Roast the shells in the oven for 10 minutes until they become completely dry, turn a vibrant red, and smell intensely of toasted crustacean.
Transfer the hot roasted shells to a heavy saucepan. Add the cubed butter, water, tomato paste, and cognac. Simmer over the lowest possible heat for 40 minutes, stirring occasionally to prevent the milk solids from sticking to the bottom.
Line a fine-mesh sieve with cheesecloth and set it over a heatproof bowl. Pour the hot butter mixture through the sieve, pressing firmly on the shells with a spatula to extract every drop of liquid and flavor. Discard the spent shells.
Transfer the strained butter to the refrigerator for 15 to 20 minutes. Once it begins to solidify but is still soft and pliable, stir in the sea salt. Mix thoroughly to re-incorporate the milk solids and water evenly into the butterfat.
Spoon the semi-firm butter onto a sheet of parchment paper. Roll it into a tight log, twist the ends to seal securely, and chill in the refrigerator for at least 40 minutes until completely firm before using.
Chef's Notes
- Roasting the shells first is a non-negotiable step. It enhances the deep, savory crustacean flavor, caramelizes residual proteins, and drives off any unpleasantly fishy aromas.
- Adding a small splash of water during the infusion acts as a temperature buffer. Because water boils at 100 degrees Celsius, it prevents the butter from exceeding this temperature until all the water evaporates, protecting the milk solids from burning.
- For an even longer shelf life or if you prefer a completely translucent finish, you can use clarified butter instead of whole butter, though whole butter provides a creamier, richer mouthfeel.
- Ensure you crush the shells as thoroughly as possible before roasting. Smaller pieces mean a larger surface area, which translates to a more efficient extraction of color and flavor.
Storage
Refrigerator: 2 weeks — Wrap tightly in parchment paper or store in an airtight ramekin to prevent absorbing fridge odors.
Freezer: 3 months — Slice into single-serve medallions before freezing for easy portioning.
