Grease loaf pan with shortening, line pan bottom with parchment paper, then grease parchment paper. Flour the whole pan.
In a medium bowl, sift together the flour, baking powder, and salt.
In a large bowl, whisk together the yogurt, 1 cup of sugar, eggs, 2 tsp of the orange zest, and vanilla.
Whisk the dry ingredients into the wet ingredients and add canola oil, whisking until fully incorporated.
Pour batter into prepared pan and bake for 50 minutes, or until toothpick inserted in middle comes out clean.
Meanwhile, in a small saucepan, cook the remaining ⅓ cup sugar and the ⅓ cup orange juice over medium heat until sugar dissolves and mixture is clear.
When cake is done, allow it to cool for 5 minutes. Then run a butter knife around the sides to loosen it. Turn it out onto a baking rack positioned over a sheet pan. Turn upright.
Poke holes in the top using a thin skewer. Pour sugar/orange juice mixture over the top, making sure some seeps into the holes. If any begins to pool at bottom, you can smear that into the sides of the cake to make sure the cake gets a nice layer all around.
Just before serving, stir the confectioner's sugar, 2 Tbsp orange juice, and remaining 1 tsp orange zest in a medium bowl. Drizzle over cake.
Notes
Because the cake itself doesn't have any butter in it, it's best to grease the pan with shortening because it won't affect the flavor and helps the cake to brown nicely.
Recipe by Simple, Sweet & Savory at https://www.simplesweetsavory.com/orange-yogurt-cake/