Heat oven to 350°F. Pulse freeze-dried strawberries in a food processor until ground into a fine powder. Rub the base and sides of the fluted loaf pan with butter and set aside.

In a large mixing bowl, add flour, sugar, baking powder, baking soda and salt. Whisk to combine.

Add melted butter, eggs, sour cream, vanilla extract and Champagne. Stir until just combined, then divide the batter evenly into 3 bowls.

In the first bowl, stir in 3 tablespoons of freeze-dried strawberries and, if using, a few drops of red food coloring. Stir until combined, adding more food coloring as needed—you want it to be a dark pink color.

In the second bowl, stir in 1 tablespoon of freeze-dried strawberries and a drop or two of red food coloring. Stir until combined and a lighter pink in color.

Pour the darkest batter into the bottom of the fluted loaf pan. Add the lighter pink batter on top and spread into an even layer. Top with plain batter, again spreading into an even layer. Sprinkle the entire top of the loaf with demerara sugar and bake for 40-45 minutes, until a cake tester comes out clean.

If glazing, let the cake cool, then mix powdered sugar with 2 tablespoons of champagne and 1 tablespoon of leftover freeze-dried strawberry powder. Stir until smooth, adding more Champagne as needed to make it a drizzling consistency. Drizzle glaze on top of the cake and sprinkle with more freeze-dried strawberry powder to finish.