Preheat oven to 375 degrees F (190 degrees C). Grease a baking sheet with cooking spray.
Mix flour, sugar, baking powder, baking soda, and salt together in a large bowl; add softened butter and mix until evenly moistened.
Make a well in the center of the flour mixture. Pour 1 cup buttermilk, egg, and 1/4 cup Irish cream liqueur into the well; add raisins to the buttermilk mixture. Knead mixture until raisins are spread throughout the dough. Form dough into a disk and cut an 'X' into the top of the dough; place onto prepared baking sheet and set aside.
Melt butter in a small saucepan over medium-low heat. Stir 1/4 cup buttermilk and 1/4 cup Irish cream liqueur into the melted butter until smooth; remove from heat and generously brush liquid over the dough.
Bake in preheated oven, brushing liquid onto loaf every 15 minutes, until no longer doughy in the center, about 45 minutes. Let bread cool on pan for 10 minutes before moving to a cooking rack to cool completely.