How to Make It
Steep tea bags in 1 cup cold water 30 minutes; remove and discard tea bags. Combine tea, raspberries, and sugar in a blender; process until smooth, about 30 seconds. Pour through a fine wire-mesh strainer into a large pitcher. Discard solids. Stir in gin. If not serving immediately, seal well with plastic wrap, and refrigerate up to 8 hours or overnight.
When ready to serve, stir well. Add sparkling rosé, and stir gently to combine. Pour into 4 collins glasses or mason jars filled with ice, and garnish with fresh raspberries.