In the bowl of a stand mixer with a paddle attachment, cream the butter, sugar, and Rodelle Lemon Extract until light light and fluffy. Beat in Rodelle Vanilla Extract and salt until combined. Beat in eggs one at a time, making sure to fully incorporate before adding the next egg. Scrape down the sides of the bowl.
Add the flour and baking powder, blend on low-speed until almost fully incorporated. Remove bowl from mixer.
Add the berries and gently fold in until fully combined.
Grease and line a 9-inch cake pan with parchment paper.
In the bowl of a food processor, with all-purpose blade, combine streusel topping ingredients and pulse until mixture resembles course crumbs.
Distribute the streusel topping evenly over the surface of the cake batter.
Bake for 50-60 minutes, or until toothpick inserted in center comes out clean.
