Preheat oven to 350 degrees. Generously grease and flour a 10-inch bundt pan. Set aside.
In a large mixing bowl, beat butter and sugar with an electric mixer until light and fluffy – approximately 2 minutes.
Add eggs, one at a time, beating after each addition until well combined. Scrape down the sides of the bowl with a spatula as needed.
Beat in buttermilk, lemon zest and vanilla until combined. Set aside.
Whisk together flour, baking powder, baking soda and salt in a separate bowl.
Slowly add dry ingredients to wet, beating on low speed until just combined. Avoid overmixing. Note: batter will be thick.
In a separate bowl, toss raspberries with 2 Tablespoons of flour until coated to prevent sinking while baking.
Add flour-coated raspberries and chopped white chocolate to batter, gently folding them in with a rubber spatula until evenly distributed.
Spoon batter into prepared bundt pan then level the top with a spatula.
Bake 55 to 60 minutes tenting with aluminum foil halfway through to prevent overbrowning. Cake is done when a tester inserted into the cake's center comes out clean. Take care to avoid overbaking.
Allow cake to cool for 20 minutes in the pan then turn out onto a wire rack to cool completely before adding glaze.