Spring Leek Soup with Gruyere Toasts

2 T. butter

3 large leeks white and light green parts, sliced in half longwise, rinsed and thinly sliced crosswise

pinch fine sea salt

4 C. chicken stock

pinch ground white pepper

1/2 Meyer Lemon juice and zest

4, 1/2- inch slices crusty bread toasted

3 ounces Gruyere cheese shredded

1 green onion thinly sliced (for garnish)

 

Preheat broiler. Melt butter in a large saucepan over medium heat. Add leeks and a pinch of sea salt, to help sweat out the liquid. Cook and stir until leeks are tender but not brown, about 3 minutes. Add stock and white pepper, bring to boil. Stir in lemon juice and zest. Remove from heat and season to taste with salt and white pepper. Ladle soup into 4 broiler-safe serving bowls. Place one slice of toasted bread over each serving, pressing it down to submerge. Divide cheese evenly, sprinkling it over each toast. Place bowls under broiler and broil until cheese is melted and bubbly. If desired, garnish each serving with green onion. Serve.