Make Biscuits. Preheat oven to 400 degrees. Combine the flour, baking soda, and baking powder. Grate the cold butter into the flour mixture and cut in until it is pea-sized. Add egg and mix until you get a crumbly dough. Add buttermilk a little at a time until dough forms. Cut out 12 biscuits about 1/2 inch thick. Brush on egg wash and cook for 15 minutes.
Cook Strawberries. This is optional. Fresh strawberries work well too. In a saucepan over medium heat, combine strawberries and water. Cook until strawberries are tender and cool before placing in the parfaits.
Build your parfaits. On the bottom of a mason jar place a heaping spoonful of yogurt, followed by a heaping spoonful of strawberries. Cut one biscuit into four pieces and arrange in the parfait. Top the biscuit with an additional heaping spoonful of yogurt, followed by another heaping teaspoon of strawberries.