Preheat the oven to 175 C. Line a 9x5 inch loaf tin with non-stick baking paper and set aside.
Beat the butter and sugar in a mixing bowl with a hand mixer on low speed till light and creamy. Add the eggs and vanilla beat well till combined.
Sift in the flour and baking powder, and use a spatula to fold the batter together until combined. Be gentle and don't over-mix the batter. Use a hand mixer on low speed to smoothen it out if needed.
Finally, fold in the chopped pineapple. If a spoon or two of syrup goes in along with it, that's fine :)
Bake for 30 to 35 mins, until a toothpick poked in the center comes out clean and the top is golden-brown. The cake does not rise super tall.
Let the cake cool in the tin for 20 minutes, then use the paper overhang to lift it out and place on a wire rack to cool completely.
In the meantime, spread the coconut out in a single layer on a baking tray lined with a silicone mat. Bake in a preheated oven at 175 C for 8 to 10 minutes until browned, stirring the coconut often to ensure it doesn't burn because the edges will brown faster than the center. Set aside to cool completely.
To make the filling, beat the cream and vanilla with a hand mixer on medium high speed until it forms soft peaks, and keep it chilled till needed. I didn't feel the cream needed to be sweetened, but if you prefer, add 1 to 2 tablespoons caster sugar before you whip it.
Slice the cake horizontally with a long serrated knife and gently lift and place the top half on a separate plate. Spoon half of the pineapple syrup (about 3 tablespoons) over the lower half of the cake, spreading it around evenly. The idea is to moisten it but not make it soggy. Now spread about a quarter of the whipped cream over it, followed by half the pineapple pieces. Don't crowd this layer with too much pineapple, the cake becomes harder to cut. See photos below.
Now gently turn the top half of the cake over, spoon the remaining syrup on the underside, then flip it back and place on the lower half of the cake, pressing it down gently to help it stick to the cream and pineapple.
Spread the remaining whipped cream all over the top and sides of the cake, then sprinkle the toasted coconut all over the surface. Add more coconut on the sides of the cake too. Decorate the top with the remaining pineapple pieces.
Refrigerate the cake for at least 30 minutes to give it a chance to set. Then slice into 8 thick pieces using a sharp knife for the neatest cuts. All said and done, the fruit and cream makes for a messy-in-a-good-way cake for sure!
Store in the fridge for 3 to 4 days, letting the cake sit at room temperature for about 30 minutes before eating as butter cakes firm up in the fridge. Personally I think this cake is best on the day it's made because the cream consistency changes once stored in the fridge, but it'll still taste great. Drizzle individual pieces with leftover pineapple syrup, trust me, it's so good :) Happy baking!