Slice the peppers into quarters, removing the stems and seeds. Toss with a bit of olive oil, salt, and pepper. Grill peppers, a few minutes on each side. Let cool and chop into 1/2-inch pieces.
Make the dressing: whisk together the garlic, vinegar, olive oil, mustard, and pinches of salt and pepper. Taste and adjust seasonings. Set aside.
In a large bowl, toss together the grilled peppers, cucumber, chickpeas, basil, oregano, shallot, pine nuts, cheese, if using, and as much dressing as you like, tasting as you go. This salad is best if you let it sit for 20-30 minutes in the fridge for the flavors to develop.