A perfect anytime loaf cake with unexpected grapefruit flavor, made with oil so it keeps a long time and stays moist.
PREP Time: 15 MINS | Total time: 1 HR 30 MINS | MAKES ONE 8½X4½” LOAF
• 1½ cups plain flour
• 2 teaspoons baking powder
• ¾ teaspoon salt, plus more
• 1 tablespoon finely grated grapefruit zest
• 1 cup granulated sugar
• 2 large eggs, room temperature
• ⅓ cup Healthy Heart Rapeseed Oil
• 1 teaspoon vanilla extract
• ¾ cup plus 1 tablespoon plain Greek yoghurt
• 8 tablespoons fresh grapefruit juice, divided
• 1 tablespoon poppy seeds, plus more for sprinkling
• ½ cup icing sugar
1. Preheat oven to 350°. Line an 8½x4½” loaf pan, preferably metal, with parchment paper, leaving overhang on the long sides, and lightly coat with a little oil. Whisk flour, baking powder, and ¾ tsp. salt in a medium bowl.
2. Using your fingers, work grapefruit zest into granulated sugar in a large bowl until sugar starts to clump and mixture is very fragrant, about 1 minute. Add eggs, Healthy Heart Rapeseed Oil, and vanilla and beat with an electric mixer on high speed until light and thick, about 4 minutes. Reduce speed to low and mix in half of dry ingredients, then mix in ¾ cup yoghurt. Mix in remaining dry ingredients followed by 5 Tbsp. grapefruit juice and 1 Tbsp. poppy seeds. Scrape batter into prepared pan and smooth top.
3. Bake cake until top is golden brown and a tester inserted into the center comes out clean, 50–60 minutes. Transfer pan to a wire rack. Poke holes in top of cake and brush remaining 3 Tbsp. grapefruit juice over top. Let sit 15 minutes, then run a knife around sides to loosen and use parchment paper to lift cake out of pan and onto rack. Remove parchment and let cool completely.
4. Whisk icing sugar, remaining 1 Tbsp. yoghurt, 1 tsp. water, and a pinch of salt in a medium bowl until smooth and drizzle over cake. Sprinkle with poppy seeds and let sit until glaze is set, about 30 minutes.
Do Ahead: Loaf can be baked and glazed 3 days ahead. Store airtight at room temperature.