Preheat oven to 375 and place rack in top third of the oven. Line baking sheet with parchment paper, Whisk 2 T sugar and 1 T lemon juice in a bowl for the glaze. Set aside. In a large bowl, whisk flour, baking powder, lemon peel, salt, and 1 C sugar. Add chilled butter by using your fingertips to rub it into the mixture until coarse meal forms. Add the cranberries and walnuts. Add 1/2 C of half and half and 1 T lemon juice. Toss with a fork until dough comes together in moist clumps, adding more half and half if the dough is too dry. Gather dough into a ball; divide in half. Press out each half on a floured surface until they’re about 6-inches in diameter and 1-inch high rounds. Cut each round into 6 wedges. Transfer to a baking sheet and brush with glaze. Bake until golden, about 18 minutes. Serve warm or at room temperature.