Prep the oven and pan. Heat the oven to 350°F (175°C).
Generously butter every nook of a 10–12 cup Bundt pan, then dust with flour and tap out the excess. A thorough coat helps the cake release cleanly.
Whisk dry ingredients. In a large bowl, whisk flour, baking powder, baking soda, and salt. This evenly distributes leavening for a consistent rise.
Combine sugar, zest, and eggs. In another bowl, rub the orange zest into the sugar with your fingertips until fragrant and slightly damp.
Add eggs and whisk until thickened and pale, about 1 minute.
Add fats and flavor. Whisk in melted butter, oil, vanilla, and orange juice until smooth. The blend of butter and oil gives both flavor and long-lasting moisture.
Mix in dairy. Whisk in milk and yogurt until evenly combined. The batter should look silky and pourable.
Bring it together. Add the wet mixture to the dry ingredients.
Gently fold with a spatula just until no dry streaks remain. Avoid overmixing to keep the crumb tender.
Fill the pan. Pour the batter into the prepared Bundt pan and smooth the top. Tap the pan on the counter a couple of times to pop large air bubbles.
Bake. Bake 45–55 minutes, until the top is golden and a skewer comes out mostly clean with a few moist crumbs.
Start checking at 45 minutes.
Cool and release. Let the cake cool in the pan on a rack for 12–15 minutes. Run a thin, flexible spatula around the edges and center tube. Invert onto a wire rack and lift the pan.
Cool completely.
Glaze. In a bowl, whisk powdered sugar, orange juice, zest (if using), and a pinch of salt until thick yet pourable. Drizzle over the fully cooled cake, letting it drip down the ridges.
Set and serve. Allow the glaze to set for 15–20 minutes. Slice with a serrated knife for neat cuts.
Serve as is or with lightly sweetened whipped cream.