Mexican Chocolate Streusel Cake

Ingredients

• 1 (18- or 19-oz.) pkg. Mexican chocolate
• 1 large egg yolk
• 1/2 tsp salt
• 7 Tbsp unsalted butter, at room temperature
• 1 cup all-purpose flour
• 1-3/4 cups all-purpose flour
• 1-1/4 tsp baking powder
• 1 (8-oz.) pkg. cream cheese, at room temperature
• 1 cup unsalted butter, at room temperature
• 2/3 cup granulated sugar
• 4 large eggs, at room temperature
• Powdered sugar, for dusting cake