Preheat oven to 325°F.
Combine the crystallized ginger and water in a heavy saucepan. Cook over high heat, stirring constantly until water is mostly evaporated and mixture is thickened and sticky, at least 10 minutes. Remove from heat and stir in the heavy cream.
Mix the flour, brown sugar, honey, and egg together in a separate bowl. Then stir in the ginger mixture. Pour this mixture into the prepared crust. Thinly slice the butter and arrange the pieces over the top of the filling.
Place pie on the lower-middle rack of the oven and bake for 35-40 minutes. Cool to room temperature before cutting.
