Start by cutting the oranges in half, cut them into 4 equal-sized pieces, then into dices. Transfer them to a bowl.
With a hand mixer, beat these oranges into a juice. If you don't have a mixer, you can use a blender.
In another bowl, place the eggs, the sugar, beat very well with an electric mixer or whisk, until it forms a white mixture. Add the oil, the milk and some orange zest, mix very well with a spatula or whisk.
Add the orange juice we've just beaten and mix it all together very well again. Add the wheat flour, but don't add it all at once - add it gradually, always mixing. Add the baking powder and gently mix it all together until a smooth and uniform batter is formed.
Transfer ¾ of this batter to a baking dish greased with butter and flour. Into the bowl with the rest of the batter, add the instant coffee and mix very well.
With a spoon, evenly distribute this coffee mixture all over the batter into the baking dish.
Get a toothpick and run it all over the surface of the batter, distributing the coffee mixture we've just added.
Bake in a preheated oven at 200°C (392°F) for 40 to 50 minutes (baking time may vary depending on the power of your oven).
Once it has baked through, pour the milk all over it, while the cake is still hot.
Finally, top it with some grated coconut.
Serve.