Preheat your oven to 350°F. Grease a 9 x 13–inch baking dish and line with parchment paper, letting the excess hang over the sides. (You’ll use this to pull the cake out of the pan)
In the bowl of an electric stand mixer fitted with the paddle attachment, add the butter, sugar and orange zest and mix on medium for about 5 minutes or until light and fluffy. Scrape the sides and bottom of the bowl. Add in the eggs, one at a time, making sure the first is well blended before adding the second. Take out of the mixer and set aside.
In a medium bowl, whisk together the flour, baking powder, baking soda and salt. In a liquid measuring cup whisk together the water and the sour cream. Alternate adding the flour and the water mixture to the butter mixture in two batches, mixing each addition until just combined. Fold in the cranberries until you see streaks of cranberries and they’re not completely combined. Pour into the prepared baking pan, smoothing the top with the back of a spoon. Crumble the streusel over the top and bake in the center of the oven for 60 minutes.