Potage, a thick soup developed in the peasant kitchens of medieval France, has always been a gourmet dish made from what's handy. In the Boston area, where chef Matthew Gaudet has set himself up at Cambridge's West Bridge restaurant, fresh seafood piles up high in morning markets. But to set his restaurant apart from local chowder champions and pay homage to the Gallic traditions he picked up on his French honeymoon, Gaudet put a seafood potage on his menu.
"Having mussels cooked creamy in hard cider is one of the great food memories we took back," says the chef, who curated his dish from local clams, mussels, calamari, and sea urchin.
Gaudet says that cooks interested in making his version of seafood potage at home can keep things hassle-free by not removing shells and setting their burners low while adding the thickening agent, or "liaison" – in this case, crème fraîche and egg yolks mixed and added together "so that the yolks don't scramble." Ultimately, Gaudet admits, it's pretty easy to cook this rich and slightly cidery fish soup, which tastes great with various kinds of seafood. Just ensure those indolent mussels don't stay clammed up after cooking, and you're set with the best alternative to chowder this side of the chilly Beantown (and Brittany) shores.
- 24 pieces cleaned (debearded) fresh mussels
- 24 pieces scrubbed and purged fresh little neck clams
- 1 lb calamari tubes only (opened flat and sliced into very thin strips resembling noodles)
- 3 shallots finely diced
- 2 tbsp whole butter
- 16 oz hard cider
- 16 oz vegetable stock
- 8 oz liaison (5 oz crème fraîche and 3 egg yolks)
- 10 oz uni butter (6 oz butter and 4 oz sea urchin roe, mixed well)
- 2 oz chopped chives
- 8 slices baguette
- Salt and pepper to taste
- A few celery leaves
Mix the liaison and uni butter until they are both smooth.
Warm two sauté pans large enough to hold all the mussels in one and all the clams in the other. Lay them down in a flat layer with the butter and shallots over medium high heat.
Once the shallots have softened, add the cider and cover; steam the mussels and clams until they open.
Once open, strain and reserve the juices, and remove the meat from the shells.
When ready to serve, briefly heat the reserved liquid and vegetable stock with the squid, clams, and mussels over medium-low heat until the squid is cooked.
Add the liason, and swirl into the juices. The eggs in the mix will cook and start to thicken the sauce; be careful not to boil hard or they will scramble.
When the potage starts to thicken, add 6 oz of uni butter and the chives.
Once the uni butter is swirled in and emulsified, transfer the potage to bowls.
Spread the remaining 4 ounches of uni butter on the baguette slices, and grill.
Place one slice of grilled bread in each bowl containing potage, and garnish each bowl with celery leaves.