Parbake the piecrust at 350°F until golden, about 18 minutes.
Combine flour, light brown sugar and ¼ t salt. Stir in 6 T melted butter to create a knobby streusel.
Cook the apples, sugar, cinnamon, lemon juice and a pinch of salt in remaining 2 T butter until soft, 5-7 minutes. Cool and stir in Chobani.
Turn apple mixture into piecrust, top with streusel and bake at 350°F until golden and apples are juicy, about 25-30 minutes. Cool before serving.