1) Preheat the oven to 190C/Gas Mark 5.
2) In a medium saucepan, combine the berries, lemon juice, and 3 tablespoons sugar. Place over medium heat and cook until just boiling, about 5 to 6 minutes. Remove from heat and allow to cool.
3) Place the flour, 155g sugar, and baking powder in a food processor and pulse quickly to blend. Add the cold butter and pulse quickly until the mixture resembles fine bread crumbs. In a separate bowl, beat the egg, almond extract, and milk until smooth. With food processor going, add the liquid all at once and blend 10 to 15 seconds, until the ingredients just form a ball. Remove the dough from the processor to a well-floured cutting board.
4) Shape the dough into a log about 28-cm long and 3-cm round. Grease a cookie sheet with the remaining 15g butter and lay the log in a round in center. Place in the preheated oven and bake until light golden brown, about 30 to 35 minutes. Remove from the oven and allow the dough log to cool to room temperature. Cut into slices about 2 1/2-cm thick. Top each slice with 2 tablespoons of berry compote and serve.