Mussels and Fries with Mustard Mayonnaise

While there's no substitute for eating a bowl of mussels on France's Atlantic coast, you'll be surprised at how easy it is to re-create this briny, aromatic dish at home. Moules-frites is not as difficult as you'd suspect. The trick to making really great French fries at home is frying from frozen. This allows them to crisp up on the outside just enough and reheat the interior. Then dinner can be like a night at your favourite bistro, even if you're home.

1 (15-16 oz) pkg frozen French fries
1 small onion
2 cloves garlic, forced through a press
3 Tbsp. butter
2 tsp. dry mustard
2 tsp. water
½ cup mayonnaise
1 cup dry white wine
2 lbs cultivated mussels, rinsed
2 Tbsp. fresh flat-leaf parsley, chopped

Accompaniment:
crusty bread (preferably a baguette)

Cook french fries according to package instructions and keep warm in oven if necessary.

Meanwhile, cut onion into very thin slices with slicer, then cook with garlic and a pinch kosher or sea salt in butter in a wide heavy medium pot over medium-high heat, covered, stirring occasionally, until pale golden.

While onion cooks, whisk together mustard and water until smooth, then whisk in mayonnaise and ¼ tsp. pepper.

Add wine to onion and briskly simmer, covered, stirring occasionally, until onion is almost tender, about 5 minutes. Add mussels and cook, covered, stirring occasionally, until mussels just open wide, 4-6 minutes, checking frequently after 4 minutes and transferring as cooked to a bowl. (Discard any mussels that remain unopened.)

Stir parsley into cooking liquid and season with salt. Pour liquid over mussels, then serve with fries and mustard mayonnaise.

Makes 2 servings.

Cook's Notes: This recipe can be doubled in an 8 qt heavy pot.