Preheat oven to 350° Grease mini loaf pans, muffin pans, or a regular loaf pan.
In a medium bowl, cream together the butter and sugar. Add in the eggs and milk. Add in the flour and baking powder.
Once all is combined, carefully fold in the berries.
Pour batter evenly into greased pan(s), about 2/3 full.
Place pan(s) in preheated oven, 350° for about 70 minutes if regular loaf, 35 minutes if mini loaves, or 30 minutes if muffins.
Remove from oven once toothpick comes out clean when inserted in center of bread.
Allow to cool slightly before removing from pans and serving.
Remember, cooking times may vary depending on ovens, so test doneness about 10 minutes before stated cooking times.