Preheat your oven to 350°F (175°C) and grease a 9-inch pie dish with butter or cooking spray.
Mix 1 cup of all-purpose flour with a pinch of salt and a tablespoon of melted butter to create a crust, if desired, and press into the bottom of the pie dish.
In a large mixing bowl, combine 1 cup of honey, 1 cup of Greek yogurt, and 2 large eggs. Whisk until smooth, then add 1 teaspoon of vanilla extract, 1 teaspoon of ground cinnamon, and 1/2 teaspoon of salt.
Gradually add 1 cup of all-purpose flour, stirring gently until just combined. Then pour in 1/2 cup of milk and 1/4 cup of melted unsalted butter, mixing until smooth. Fold in walnuts if using.
Pour the honey filling into the prepared pie dish and spread evenly. Bake for 30-35 minutes until the top is golden brown and a toothpick comes out clean.
Allow the pie to cool for at least 15 minutes before serving. Dust with powdered sugar if desired.