I reimagined this raspberry jam coffee cake from Kleinworth Company. I think the streusel is the best part, so I pretty much doubled it and played with the method a bit. Same with the cake. This was a solid recipe for sure. Huge thanks.

Ingredients

For the Streusel

227g unsalted butter, soft but not melted
270g flour 
135g brown sugar
135g granulated sugar
4 tsp ground cinnamon

Coffee Cake

200 g flour
2 tsp baking powder
½ tsp salt
84 g butter, room temp (6 tablespoons)
150 grams sugar
2 large eggs, room temp
2 tsp vanilla extract
60 grams sour cream
120 grams buttermilk
160 grams fruit preserves (1/2 cup)

Glaze

3 tbsp milk
200 grams powdered sugar

Instructions

Preheat the oven to 350F degrees.

Grease a 9″ round springform pan with nonstick cooking spray. Set aside.

In a medium bowl, make the streusel by combining flour, sugars, cinnamon and butter.

Mix together until mixture forms a ball and then crumbles in your fingers. Set aside. 

For the Cake, combine flour, baking powder, and salt in a large bowl. Set aside.

In a large mixer bowl, combine butter and sugar on medium speed until fluffy. 

Add in the eggs and vanilla, continue beating until combined. Turn off mixer. 

Fold in sour cream. Then fold in flour mixture and buttermilk. Gently combine. 

Pour batter into the prepared pan. Place dollops of preserves on top of the cake batter & cut a knife through to create swirls. Sprinkle the streusel on top.

Bake in your prepared oven for 50 to 60 minutes, or until toothpick test is clean.

Make the glaze, whisk together the milk and powdered sugar until a smooth

Drizzle cake on cake when cooled.