Begin by dicing the English cucumbers into small, uniform pieces and sprinkle lightly with salt. Let sit for 10 minutes to draw out excess moisture.

In a large mixing bowl, combine yogurt, crumbled feta cheese, and fresh herbs. Add lemon zest and juice, and mix until well combined.

After 10 minutes, drain excess liquid from cucumbers and pat dry. Fold cucumbers into the yogurt mixture until well coated.

Take two slices of bread, layer sprouts, then spread the cucumber salad filling. Add thinly sliced onion, then top with the second slice of bread.

Serve immediately to enjoy the freshness. For later, store filling separately from bread to maintain texture.