1. In a pot, gently boil potatoes in salted water until nearly done, about 15-20 minutes.
2. Strain potatoes and place on a clean towel. Let them cool for 5 minutes.
3. Cover potatoes with another clean towel. Use a cooking mallet to gently smash each potato just enough to flatten, but keeping intact. This can be done day ahead and cooled in fridge.
4. In a large skillet over medium- heat, cook the chopped bacon until almost fully crispy. Add the smashed potatoes to the pan and fry carefully on each side until golden brown, about 3 minutes per side. About halfway through, add rosemary to the pan. Season lightly with salt and pepper.
5. Transfer potatoes to a plate lined with paper towels and then arrange potatoes on a platter. Add dollops of garlic aioli on top of potatoes, then sprinkle with cooked bacon. Serve and enjoy!