Preheat oven to 350°F (175°C). Grease and flour a 9x13 inch baking pan.
In a large bowl, whisk together flour, sugar, baking powder, baking soda, and salt.
In a separate bowl, cream together butter and sugar until light and fluffy. Beat in eggs one at a time.
Gradually add the dry ingredients to the wet ingredients, alternating with the buttermilk, beginning and ending with the dry ingredients. Mix until just combined.
Stir in lemon juice and raspberries.
Pour batter into prepared pan and bake for 45-50 minutes, or until a wooden skewer inserted into the center comes out clean.
Let cool completely before serving.
Notes
This cake is best served fresh, but can be stored in an airtight container at room temperature for up to 3 days.