Pre-bake your pie case to the recipe of your choice. Follow the instructions you have on hand for blind-baking.
In a large mixing bowl add the egg yolks and beat on high speed until they are light and fluffy. They should look like whipped butter.
Slowly add in the sugar beating constantly and scraping down the sides.
Once the butter is fully incorporated slowly add in the sifted flour. The egg mixture will be thick at this point and may stick to the sides and bottom of your bowl. Ensure you are scraping with a rubber spatula to fully incorporate. Beat for about three minutes until fully incorporated.
Slowly stream in the melted butter, continuing to beat the mixture.
Next, whisk in the buttermilk, baking soda, lemon juice, and vanilla by hand. Whisk to ensure all the egg mixture is well incorporated and the filling is smooth.
Slowly pour the filling into the prepared pie crust. We recommend placing the pie to bake on a baking sheet to catch any potential overflow.
Cover the pie crust edges with foil or crust shield to prevent over-browning.
Bake at 220°C for 10 minutes. Reduce heat to 180°C degrees and bake for another 35 to 40 minutes or until the centre is set.