Preheat the oven to 350 degrees F. Generously coat a 9-inch round springform pan with cooking spray, or line a 9-inch round cake pan or 8x8 inch square pan with parchment paper and spray with cooking spray.
Make the streusel topping: In a medium bowl, mix the flour, brown sugar, and cinnamon. Add the melted butter and stir together with a fork until it resembles clumps of wet sand. You may need to use your fingers to form the mixture into nice thick clumps. Cover the bowl with plastic wrap and place in the fridge for later.
Mix the wet ingredients: In a large bowl, whisk the olive oil, Greek yogurt, maple syrup, eggs, orange zest, orange juice, and vanilla extract until smooth and well combined, about 1 minute.
Prepare the dry ingredients and mix-ins: In a medium bowl, whisk the flour, baking powder, baking soda and salt. Add the dry ingredients to the wet ingredients and use a wooden spoon to mix until combined, do not overmix. Fold chocolate chips into the batter.
Transfer the batter to the prepared pan and spread into an even layer. Evenly sprinkle the streusel on top.
Bake the cake: Bake until a tester inserted into the middle comes out clean with just a few crumbs attached, 40 to 50 minutes. Allow the cake to cool almost completely before glazing.
Make the glaze: Once the cake is cool, you can make the glaze. In a small bowl, add the powdered sugar, orange juice and zest and mix together with a fork until well combined, smooth and can easily be drizzled. Drizzle back and forth over the cake. Cut into 10 to 12 slices, then enjoy. Serve with Greek yogurt for protein, or if serving for a dessert I recommend serving with a scoop of coffee or vanilla flavored ice cream.