1/3 cup vegetable oil
1 tablespoon Sriracha (hot chili sauce)
1 tablespoon toasted sesame oil
8 cups matchstick-size pieces mixed summer vegetables (such as carrots, radishes, cucumbers, and bell peppers; about 1 1/4 pounds)
Kosher salt, freshly ground pepper
8 ounces buckwheat soba (Japanese-style noodles) or vermicelli noodles
1 cup (loosely packed) cilantro leaves with tender stems
3 scallions, thinly sliced
1 tablespoon black or white sesame seeds
Whisk first four ingredients in a large bowl. Add vegetables; toss to coat. Season with salt and pepper.
Cook noodles in a large pot of boiling salted water, stirring occasionally, until al dente; drain. Run noodles under cold water to cool them; drain well and add to bowl with vegetables. Add cilantro and scallions; season to taste with salt and pepper. Sprinkle sesame seeds over and serve.