Spray counter lightly with non-stick cooking spray. Flatten each Texas roll or 2 dinner rolls combined into a 3-inch circle. Place on a large sprayed baking sheet and brush tops of rolls with egg white. Cover with sprayed plastic wrap and let rise until double in size.
Place pistachios on a plate. Remove wrap and dip rolls, top side down in pistachios, patting gently to adhere. Return rolls to baking sheet.
With scissors or knife, make 5, 3/4-inch deep, cuts evenly around outside edge of each roll to resemble flower petals. With fingertips, make indentation in center of each roll. Spoon 1 tablespoon preserves into each indentation.
Bake at 350°F 18-20 minutes. Remove from baking sheet and cool completely on wire rack. Combine all remaining ingredients until smooth and drizzle over cooled rolls..