Combine tomatoes, pepper, cucumber, onion and garlic in a blender. Blend until very smooth, at least 2 minutes, scraping down sides as needed.
STEP 2
With the motor running, add vinegar and salt. Slowly drizzle in olive oil until the mixture is smooth and emulsified. Adjust thickness with more olive oil if needed.
STEP 3
Strain the mixture through a strainer or food mill into a glass pitcher. Chill for at least 6 hours or overnight.
STEP 4
Adjust the seasonings with salt and vinegar before serving. Serve in glasses over ice or in bowls, with olive oil drizzled on top.