Cook the barley in boiling salted water.

In a large pot, heat olive oil and sauté the onion and garlic. Add the zucchini and leek, sliced into rounds, and cook for about 10 minutes, adding a little water as needed.

Blend everything until smooth, season with salt, and strain through a fine mesh sieve to remove any lumps (you can use the solid part as a spread for crostini).

Cut the smoked salmon into pieces and set aside.

Drain the barley and add it to the creamy vegetable mixture along with the salmon. Cook over low heat, stirring, until everything is well combined and creamy.

Serve topped with grated lemon zest.