Wash the English cucumber and cherry tomatoes thoroughly under cool running water. Slice the cucumber into thin rounds, about ¼-inch thick, and halve the cherry tomatoes.

Slice the red onion thinly to create paper-thin rings and set aside.

In a mixing bowl, combine the sliced cucumber, halved tomatoes, sliced red onion, and mozzarella pearls. Mix gently to keep the ingredients intact.

Drizzle with extra virgin olive oil and balsamic glaze, then season with salt and black pepper. Optionally, sprinkle with crushed red pepper flakes.

Gently toss the salad until all ingredients are coated and refrigerate for 15 to 30 minutes before serving.