Place orange chunks in a saucepan, cover with water, bring to a boil, then simmer for 20 to 25 minutes until very soft. Drain, cool slightly, and blend until smooth.

Preheat oven to 350°F (180°C) and line a 9x5-inch loaf pan with parchment. In a large bowl, whisk eggs and sugar until pale and thick, about 2 minutes. Add oil and orange pulp, whisk until combined.

Sift in flour, almond meal, baking powder, and salt. Fold gently with a spatula just until no dry streaks remain.

Scrape batter into pan, smooth the top, and bake for 50 to 55 minutes until a skewer inserted in the center comes out clean. Tent with foil after 40 minutes if browning too fast.

Cool in the pan for 10 minutes, lift out with parchment, and cool completely on a wire rack. Dust heavily with icing sugar and slice thickly to serve.