Cut the cucumber, radishes, and tomato into a small dice (about 1/4-inch) and place in a medium bowl.

Chiffonade the basil by stacking several leaves on top of each other, then rolling together tightly; slice crosswise into thin strips. Add the basil, vinegar, and oil to the bowl. Toss to combine; season with salt and pepper.

Slice the baguettes into thin rounds. Spritz with olive oil spray and sprinkle lightly with garlic powder. Heat a grill pan or heavy skillet over high heat. Add the baguette, seasoned side down. Cook 3-5 minutes, or until the bread is lightly charred.