In a large mixing bowl, beat butter and sugar until blended. Add eggs, beating until combined. Beat in flour and baking powder. Add coconut and coconut flavoring.
Line a large baking sheet with parchment paper or silpat. Divide dough in half and shape each half into a 10inch by 2 ½inch rectangle. Use your fingertips to pat evenly. Bake in a 350 degree oven for 25 minutes. Remove from oven and cool 5 minutes.
Slice each rectangle into 10-12 biscotti. Turn biscotti slices onto a side. Return to oven and bake 8-10 minutes. Remove and flip biscotti to other side. Bake for an additional 8-10 minutes. Remove and cool.
Store cooled biscotti in airtight container for up to two weeks.