Bring 1.5L water in a large pot to boil. Add 2 tablespoons sea salt, baking soda, and potatoes and stir. Return to a boil, reduce to a simmer, and cook until a knife meets little resistance when inserted into a potato chunk, about 10 minutes after returning to a boil.
Combine olive oil with rosemary, garlic in a small saucepan and simmer on medium heat for 3 minutes. Strain oil and set aside.
When potatoes are cooked, drain carefully, and let them rest in the pot for about 30 seconds to allow excess moisture to evaporate.
Transfer to bowl with infused oil, season to taste with a little more salt and pepper, and toss to coat.
Transfer potatoes to a baking sheet and roast in oven at 220 degrees, without moving, for 20 minutes. Using a thin, flexible metal spatula to release any stuck potatoes, shake pan and turn potatoes.
Continue roasting for 30-40 minutes till golden and crispy.
Toss kale leaves in a bit of olive oil and salt and roast them with the potatoes for the last 10 min. Serve with Heinz Seriously Good Peri Peri Sauce.