- 1/2 cup olive oil
- 2 tablespoons crushed red pepper flakes
- 1 tablespoon fennel seeds
- 3 pounds large tomatoes, preferably heirloom, sliced into 1/4″-thick rounds
- 1 tablespoon (or more) red wine vinegar
- Flaky sea salt
- Cook oil, red pepper flakes, and fennel seeds in a small saucepan over medium-low heat, stirring occasionally, until oil around spices is sizzling, about 5 minutes. Reduce heat to low and continue to cook until oil is infused with flavor and rusty-orange in color, 20–30 minutes. Let cool.
- Arrange tomatoes on a large platter and drizzle with vinegar, then chile-fennel oil. Season with more vinegar if desired and sprinkle with salt.