This is a recipe I got from a Mary Engelbreit book back in the 90s.
3 1/2 cups sifted cake flour (not self-rising)
1/2 tsp baking powder
1/4 tsp salt
1 cup (2 sticks) unsalted butter, at room temperature
1/2 cup vegetable shortening
1 1/2 cups sugar
6 large eggs
1 scant cup milk
1 tbsp grated lemon zest (from about 2 lemons)
1 tsp vanilla extract
1 tsp lemon extract
Confectioners' sugar for serving
Place oven rack in the middle of the oven and preheat the oven to 300 degrees.
Grease and flour a 10-inch Bundt pan; set aside.
In a medium bowl, whisk together the flour, baking powder, and salt.
In a large bowl, cream the butter and shortening with an electric mixer. Gradually add the sugar, beating until light and fluffy. Beat in the eggs one at a time, beating well after each addition. On low speed, add the flour mixture alternately the milk, beginning and ending with the flour mixture. Stir in the lemon zest, vanilla extract, and lemon extract. Scrape the batter into the prepared pan and smooth the top.
Bake 1 1/2 hours at 300 degrees or until a toothpick inserted into the center comes out clean. Let cake cool in pan on a wire rack for 10 minutes. Invert the cake onto the rack to cool completely.
Just before serving, dust cake with the powdered sugar.