Remove your pie crust from the freezer and let it thaw at room temperature for about 10 minutes—just long enough that it’s pliable but still cold. If you’re using a homemade crust, that’s wonderful, but buy frozen to save $3 to $5 and 30 minutes of your time. Place the crust in a 9-inch pie pan. If it has a rim, you can crimp it with your fingers for a decorative edge, or leave it flat. Set the prepared crust aside at room temperature while you make the filling.

In a large mixing bowl, combine your softened butter and sugar. Using an electric mixer on medium speed, beat for about 2 to 3 minutes until the mixture is pale, fluffy, and noticeably lighter than when you started. This step is crucial—you’re incorporating air into the batter, which creates a lighter, more delicate custard. Don’t skip this step or rush it. If your butter is cold, let it sit out longer. Cold butter won’t cream properly, and you’ll end up with a denser pie. Pro tip: If you don’t have an electric mixer, use a wooden spoon and some elbow grease for about 5 minutes. Your arm will get a workout, but you’ll achieve the same fluffy texture.

Add the flour and salt to your butter-sugar mixture. Beat on medium speed for about one minute until combined. Then add your three room-temperature eggs, one at a time, beating well after each addition. The batter should look smooth and homogeneous. Room-temperature eggs blend in more smoothly than cold eggs, which means fewer lumps in your final custard. Take the eggs out of the fridge about 15 minutes before you start baking.

In a small measuring cup or bowl, whisk together the buttermilk, fresh lemon juice, and vanilla extract. Pour this mixture into your egg batter and blend on medium speed for about 1 to 2 minutes until everything is combined. Here’s where some home bakers panic: the mixture may look slightly curdled or separated, and that’s completely normal. Buttermilk and eggs naturally separate slightly when mixed, especially with acid (the lemon juice). This is not a mistake. The custard will smooth out and set beautifully as it bakes.

Pour your filling into the prepared pie crust. If you have a cookie sheet, place the pie pan directly on it. This is a professional baker’s trick that prevents the bottom crust from getting soggy or burning. The cookie sheet distributes heat more evenly under the pie and catches any drips. It’s a small step that makes a big difference in texture. Preheat your oven to 350°F if you haven’t already. If you’d like to add a small touch of richness, dot the top of the custard with tiny pieces of butter (about 1 tablespoon total, cut into small cubes). This creates a subtle, golden top, but it’s completely optional.

Place the pie (on the cookie sheet) into your preheated 350°F oven and bake for 50 to 55 minutes. You’re looking for a pie that is lightly golden brown on top and mostly set but still slightly jiggly in the very center—about a 2-inch circle in the middle should jiggle slightly when you gently shake the pan. This is the sweet spot. If you bake it until it’s completely firm and set throughout, it will continue cooking as it cools and may become rubbery. Every oven runs differently. Start checking at the 45-minute mark. If you notice the edges are browning too quickly, tent the top loosely with aluminum foil for the final 10 minutes.

Place the pie on a wire cooling rack and let it cool to room temperature—this takes about 2 to 3 hours. This cooling time is not optional; it allows the custard to set properly. If you try to slice it while it’s warm, the filling will be too soft and the slices will fall apart. I know waiting is hard, but I promise it’s worth it. Serve at room temperature, or chill it in the refrigerator for a cooler, denser texture—both are delicious.