1. Whisk olive oil, fresh lemon juice, lemon zest, minced garlic, dried oregano, salt, pepper, and red pepper flakes together in a large bowl until fully combined and slightly emulsified. This same mixture serves as both the bean marinade and the final salad dressing — no second dressing needed.

2. Add drained and rinsed white beans directly to the marinade bowl. Toss thoroughly to coat every bean. Let sit at room temperature 15–20 minutes minimum — or up to overnight in the fridge in a covered container. Stir once or twice during marinating for even coverage. The beans visibly absorb the dressing as they rest.

3. Place thinly sliced red onion in a small bowl of cold water. Soak 5 minutes to mellow the sharpness while keeping the color. Drain and pat dry. Halve cherry tomatoes, quarter and slice cucumber into half-moons, dice bell pepper, halve Kalamata olives, and chop parsley.

4. Add cherry tomatoes, cucumber, bell pepper, drained red onion, Kalamata olives, and parsley to the bowl of marinated beans. Toss everything together gently until all vegetables coat evenly in the remaining dressing. Taste and adjust — add more lemon juice for brightness, more salt if needed, or a drizzle of extra olive oil for richness.

5. Scatter crumbled feta across the top of the assembled salad. Toss gently just once to incorporate without breaking the feta into powder. Serve at room temperature or slightly chilled, garnished with extra parsley, a few whole olives, and a drizzle of good extra-virgin olive oil. Crack fresh black pepper over the top at the table.