1 cucumber, sliced thin, skinned if desired
1 purple onion, sliced thin
2 Roma tomatoes, chunked
1/4 c. rice vinegar
salt, to taste
pepper, to taste
1 tbsp. sugar
1/4 c. vegetable oil
1/4 c. water

Place all ingredients in an airtight glass jar that can be shaken before each serving. Allow several hours or overnight for the flavors to blend. This mixture does not have to be refrigerated. It can be left out at room temperature, and more ingredients added as needed.