Preheat oven to 425 degrees then line a baking sheet with a silpat or parchment paper and set aside. In the bowl of a large food processor (or in a large bowl) add flour, sugar, baking powder, and salt, then pulse or whisk to combine. Add cold butter and pulse until well incorporated and mixture is the texture of cornmeal. Alternatively, use your fingertips or a pastry butter to blend butter in. In a separate bowl, whisk together half & half, egg, and vanilla bean seeds. Add to flour mixture and pulse until just combined. Alternatively, stir until the dough comes together in a ball. Turn the dough out onto a floured surface then gently knead 4 or 5 times to bring the dough together. Roll dough into a rectangle about 1/2" thick then trim sides to make a rectangle. To make petite-sized scones: Cut rectangle into 6 rectangles, then cut each one in half diagonally. Transfer to prepared baking sheet then bake for 8-9 minutes, or until edges are just starting to turn golden brown. To make mini-sized scones: Cut rectangle into 6 rectangles, then cut each one in half diagonally. Cut each triangle in half to make 2 triangles. Transfer to prepared baking sheet then bake for 6-7 minutes, or until edges are just starting to turn golden brown. Remove scones to a cooling rack to cool completely. Meanwhile, in a large bowl, whisk together glaze ingredients. Dip cooled scones in glaze then place back onto cooling rack to harden completely.