Heat ½ & ½, cream and flavorings over med heat. Whisk sugar and yolks together. Add puree. When cream comes up to a light boil, turn off stove. Temper cream into the yolks, by slowly adding hot cream to the yolks, whisking the entire time. Add ¼ of the cream to the yolks. Pour back into the pot. Using a rubber spatula stir the cream and yolk mixture over low to med heat for 3-5 min until lightly thickened. Be sure to scrape the bottom and sides constantly. DO NOT BOIL! Remove from heat and stir for one more minute. Strain and cool in a ice bath. Freeze in ice cream machine according to manufacturers instructions.