Cut the potatoes into 4 parts and boil in salted water until tender. Chop the onion. Cut the bacon into cubes.
Place the bell peppers in a mold, sprinkle with oil, add thyme sprigs and bake in an oven preheated to 200°C for 15-20 minutes. Remove seeds and skin from the finished peppers and cut into thin strips.
In a separate bowl, combine oil, wine vinegar, salt and pepper. Add chopped onion to the dressing and let sit for a couple of minutes.
Cut the bacon into cubes and fry until crispy.
In a salad bowl, combine potatoes, peppers, capers, parsley, bacon, pour in the dressing with onions and mix gently.