The makings of a perfect weekend must include breakfast sweets, a fact well supported by our ever growing plethora of sweet breads, muffins and coffee cakes.  The one I make the most is our Apple Cake, which is awesome, and in the summer I like to use fruit and will often do a blueberry crumb cake which is also a treat.  But this weekend I wanted something substantial and classic, and this cake is the ultimate brunchy crunchy chewy cinnamony streusel and glaze topped champion of all great coffee cakes!  There’s so much that’s right about it – I really felt like I was staying at a fancy New York hotel or something with every bite- it’s simple, but has an elegant balanced delicious taste and the heavy crumb on top is the key to all breakfast cake successes.  -CK 2.0

For the Streusel:
1 3/4 cups all purpose flour
1 cup light brown sugar (packed)
1 1/4 teaspoon ground cinnamon
1/4 teaspoon coarse salt (Martha calls for an entire teaspoon, but I like it better with just a touch of the coarse salt then you get just that tingle of salty sweet, but you could also do 1/2 teaspoon of table salt)
3/4 cup cold butter cut into small pieces
1 1/2 cup coarsely chopped toasted walnuts (to toast – but on a cookie sheet in a 350 oven for about 7-9 minutes until lightly toasted and fragrant)

For the Cake:
1/2 cup butter
2 cups all purpose flour
1 1/4 teaspoons baking powder
1/2 teaspoon baking soda
1/4 teaspoon coarse salt (or 1/2 table salt)
1 cup granulated sugar
2 large eggs
1 1/2 teaspoons vanilla extract
1 cup sour cream

For the Glaze:
1 1/2 cups confectioners sugar
3 tablespoons whole milk (I used 2 buttermilk and one whole milk)

1. Make the Streusel top and middle layers: Mix together flour, 3/4 cup brown sugar, 1 teaspoon cinnamon, and the salt.  Cut in butter with a pastry blender or rub in with your fingers until small to medium clumps form.  Mix in 1/2 cup nuts.  Refrigerate topping until ready to use.  Make the streusel center:  Mix together remaining 1/4 cup brown sugar, 1/4 teaspoon cinnamon, and 1 cup nuts, reserve for layering into the center of the batter.
2. Make the Cake: Preheat oven to 350.  Butter a 9-inch tube pan with a removable bottom (you can use a springform pan also.  I used a 9×13 which is trickier to get the layer in the center to work out so I recommend a round pan).  Sift flour baking powder, baking soda, and salt into a medium bowl.
3. With an electric mixer on medium beat the butter and sugar until pale and fluffy, about 2 minutes.  Add eggs, 1 at a time, beating well after each addition.  Beat in vanilla.  Add flour mixture in 3 batches alternating with 2 batches of the sour cream.  Beat until well combined.
4. Transfer half of the batter to the prepared pan.  Sprinkle streusel evenly over batter.  Top with remaining batter; spread evenly with an offset spatula.  Sprinkle streusel topping evenly onto batter.
5. Bake until cake is golden brown and a cake tester comes out clean, about 55 minutes.  Transfer pan to a wire rack to cool completely.  Remove cake from pan; transfer to a parchment lined work surface or serving platter.
6. Make the Glaze: Mix together the confectioners sugar and milk.  drizzle over cake allowing glaze to drop down the sides.  Let sit a few minutes before serving.

Recipe adapted from Cinnamon Streusel Coffee Cake – Martha Stewart Cakes Book