Slice the onion into fine, long strips. Add the onion slices into a cold water bath and rinse them a few times.

Next, get rid of the watery inners from the cucumber and the white parts inside the tomatoes. Then, cut the cucumber and tomatoes into pieces of your preferred size.

If you don’t have stale bread on hand, tear the bread into pieces and toast it until dry.

Add the tomato and cucumber to a sieve over a little bowl and salt them to draw out excess moisture. Let them rest for about 30 minutes. Reserve the resulting liquid for the dressing.

Combine the tomato liquid, vinegar, mustard, and olive oil into a delicious, creamy emulsion by whisking them together. Check for seasoning and consistency.

Let the salad rest for at least 20 minutes while tossing it now and then. Check for seasoning before plating.