Preheat oven to 325ºF (170°C). Grease a 9x4-inch loaf pan with shortening and flour it. You can line it with a strip of parchment paper covering the bottom and the two narrow sides. It's what I do as it makes it easier to remove the cake.
Beat 9 tablespoons unsalted butter and ½ cup sour cream in a large bowl until smooth, about 1 minute.
Add 1 teaspoon lemon zest and mix.
Add 1 ½ cups sugar gradually and beat until light and fluffy, about 3 minutes more.
Add 3 eggs, one at a time, incorporating each one before adding the next.
Add ½ teaspoon vanilla extract and 2 tablespoons fresh lemon juice.
Sift 1 ⅔ cups all-purpose flour with ¼ teaspoon baking soda and ¼ teaspoon salt and add it to the butter mixture in 2 additions, beating at low speed only until well mixed. Don't overbeat.
Pour batter into the pan and smooth the top.
Bake for about 45-50 minutes, or until a cake tester or toothpick comes out clean. It might take longer depending on your oven and the type of pan you use. If the top is browning too quickly, tent with a piece of aluminum foil for the last part of the baking.
Cool for 10-15 minutes on a wire rack, run a smooth-bladed knife around the edges to loosen and remove from the pan carefully.
Let cool completely before glazing.