Streusel Apple cake

Come back home =D let's start to write my blog in English! Too many troubles i've found once back and too much need to bake =) let's start again, before my second departure :S


Ingredients
For streusel:

• 1 1/2 cups packed light brown sugar
• 3/4 cup all-purpose flour
• 1/2 cup butter, chilled and diced
• 2 teaspoons ground cinnamon
• 1 cup chopped walnuts
• For cake dough:
• 3 1/4 cups all-purpose flour
• 1 1/2 teaspoons baking powder
• 3/4 teaspoon baking soda
• 3/4 cup butter, room temperature
• 1 1/2 cups white sugar
• 3 eggs
• 2 teaspoons vanilla extract
• 16 ounces plain low-fat yogurt
• 2  apples - peeled, cored and finely diced
• 
  
• Preheat oven to 175° degrees C. Grease and flour a Bundt cake pan.
• To make streusel: In a medium bowl, mix brown sugar, 3/4 cup flour, and cinnamon. Cut in the butter with a fork until crumbly. Stir in walnuts.
• In a medium bowl, stir together 3 1/4 cups flour, baking powder, and baking soda. In a large bowl, cream together the butter and sugar until light and fluffy. Beat in the eggs one at a time, mixing well after each. Then stir in the vanilla and yogurt. Gently stir in the flour mixture just until blended.
• Pour 3 cups of the batter into the Bundt pan, sprinkle with 1/4 of the streusel, and layer with apples. Sprinkle with 1/2 the remaining streusel. Pour in the remaining batter, and top with the remaining 1/4 streusel. Lightly pat the top layer of streusel so it sticks to the cake batter.
• Bake 50 to 60 minutes in the preheated oven, or until a toothpick inserted in the center comes out clean. Cool in the pan on a wire rack 15 minutes. Place cookie sheet over pan and carefully invert both. Remove Bundt pan, and let the cake cool completely.
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