Preheat oven to 350°F / 180°C / Gas mark 4.

In a medium mixing bowl, sift together flour, baking powder, baking soda, salt and sugar. Set aside. 

Using a pastry blender or food processor cut butter into flour mixture until you have pieces no larger than a pea. Transfer mixture to a large mixing bowl.

Add raisins and currants into flour and butter mixture. Toss to coat raisins in flour.

Add milk and eggs, mix to combine with a spoon or sturdy rubber spatula. (I don't recommend food processor here).  

Dough will be sticky. Using floured hands, mold into a round or oblong loaf. (This is a quick bread and is not meant to be kneaded, take care not to overwork the dough.)

Place soda bread on baking pan lined with parchment paper in center of oven.

Bake for 50 - 60 minutes. Remove from the oven and place on cooling rack.

Brush top of soda bread with butter while hot.

Let cool completely before cutting.