Heat the oil in a large saute pan to a high heat. Cut the halloumi cheese into 8 thin slices and grill until golden on both sides.
Remove and set aside.
Add the bread and salt; cook over low to medium heat, tossing frequently, for 10 minutes, or until nicely browned.
Add more oil as needed.
For the Vinaigrette: Whisk all the ingredients together. In a large bowl, mix the tomatoes, cucumber, red pepper, yellow pepper, red onion, basil, and capers.
Add the bread cubes and toss with the vinaigrette.
Season liberally with salt and pepper.