This was surprisingly easy to make and very tasty. The trick is to infuse the oil with the rosemary while you are making it crispy and to give the chickpeas enough time to crispen themselves. It comes from Ali Slagle in NYTimes Cooking.

For this you’ll need: 1 lb spaghetti or linguine pasta, 1 14oz can chickpeas (drained, washed and dried), 4-5 sprigs of fresh rosemary, 1/2 cup olive oil, 3 cloves garlic (crushed and chopped), 3 Tbsp unsalted butter, 1/4 cup fresh parsley (chopped), 1/4 lemon, grated parmesan, salt and pepper.
Start a large pot of water on to boil for the pasta. Once it is boiling, add the pasta and cook until al dente – about 8 mins (but check package instructions). Make sure to save about 1/2 cup of the pasta water when straining.
Drain and rinse the chickpeas and place them in a single layer on a plate lined with paper towels and gently dry them using another layer of paper towels over the top.
Meanwhile, heat the oil in a large skillet over medium high heat until shimmering. Add the rosemary springs and fry, turning once (carefully!) until wilted and darkened. Remove the rosemary from the hot oil using tongs and place onto a plate lined with paper towel to dry and drain.
Add butter to the oil and gently stir until it is melted. Add the dried chickpeas and garlic to the oil/butter and toss everything together. Fry, toss/stir often, until peas are crisp – about 8-10 mins. Adjust the heat so that it is high enough but not scorching the peas – medium high should be ok.
Pinch the rosemary sprig at the top and pinch your fingers around the stem and run them down, the fried rosemary leaves should fall off easily. After they are removed from the stems, add the rosemary leaves to the oil/peas along with the chopped parsley. Reduce the heat to medium, stir well, add the cooked pasta and the reserved pasta water (about 1/2 cup), stir well again until a smooth sauce starts to form. Turn off the heat and squeeze the juice from 1/4 lemon into the pasta mixture and combine well.
Place into a large serving bowl and serve with grated parmesan.