Preheat your oven to 180° C (350° F) and grease a 22 x 13 cm (9 x 5 inch) loaf pan, lining it with parchment paper.

In a large bowl, whisk together the eggs and granulated sugar until blended. Add vegetable oil, mashed bananas, buttermilk, and vanilla; mix until smooth and creamy.

In a separate bowl, sift together flour, baking powder, and salt. Gently fold the dry ingredients into the wet mixture until lumpy.

Fold in the shredded coconut and walnuts if using, distributing evenly throughout the batter.

Pour the batter into the prepared loaf pan and bake for 45 to 50 minutes until a skewer inserted comes out clean.

Prepare the butterscotch syrup by melting brown sugar, butter, and cream in a saucepan until bubbling and caramelized.

Pierce the baked loaf with a skewer and pour the hot butterscotch syrup over it, allowing it to soak in.

Let the loaf cool in the pan for about 10 minutes, then transfer to a cutting board and slice.