Make the crumb topping: In a small bowl, whisk together the flour, brown sugar, cardamom, and salt. Pour the melted butter over the mixture, and stir with a fork until it begins to form clumps. Set aside.
Preheat the oven to 350° / 180°C / Gas mark 4. Line a 9x13 cake pan with parchment paper. Leave an overhang on either side, so you can use this to help lift the cake out later.
In a large bowl, beat the butter, sugar, and orange zest together with an electric mixer on medium speed until light and fluffy.
Add the eggs, one at a time, beating between each addition. Add the vanilla, and beat to combine.
Beat in half of the dry ingredients on low speed, followed by the buttermilk. Add remaining dry ingredients and finish with the fresh orange juice. Use a rubber spatula to scrape down the sides and bottom of the bowl.
Fold in half of the cranberries. Reserve the other half.
Spread the batter into the parchment-lined pan and use an offset spatula to smooth the top. Sprinkle remaining cranberries on top.
Top the cake with the streusel topping. Use your hand to squeeze together the sandy bits and smaller pieces, then break off larger pieces to top the cake.
Bake the coffee cake for 45 minutes, or until a toothpick inserted into the cake comes out with moist crumbs stuck to it.
Place the cake pan on a cooling rack and let the cake cool for about 30 minutes, before using the paper sling to carefully lift it from the pan, and place it back on the cooling rack to cool before cutting.