Mary's Irish Soda Bread

4 c. flour, plus more for kneading
1/2 c. sugar
1 tsp. salt
2 tsp. baking powder
1/4 c. butter (1/2 stick)
2 c. raisins
2 tbs. caraway seeds (optional)
1 1/3 c. buttermilk
1 c. sour cream
2 eggs, 1 for dough, one for brushing top of bread
1 tsp. baking soda

*Pre-heat oven to 350 degrees.
*In a large bowl, mix together, flour, sugar, salt and baking powder.
*Cut butter into dry ingredients until it becomes a bit crumbly. Add in raisins and stir until evenly distributed.
*In a second bowl, combine buttermilk, sour cream, egg and baking soda.
*Create a well in the dry ingredients and pour the wet ones in. Mix until you have a VERY sticky dough. Turn dough out onto a very well floured work surface and knead 10-12 times until combined and smooth.
*Grease a cake or small glass roasting pan with baking spray and place loaf in prepared pan. Cut an X in the top and brush with egg wash.
*Bake at 350 for an hour to an hour and 15 minutes.