Preheat the oven to 425 ̊F. Cover a baking sheet with parchment paper.

Place the flour, baking powder, sugar, and salt in a medium bowl. Add the cold, cubed butter and using your hands, rub the butter into the flour. The end result should be a flour mixture that looks crumbly with pea-sized pieces of flour-coated butter.  

To the butter-flour mixture, add the minced chives and crumbled feta. Stir briefly to combine.

In a separate bowl, whisk together the egg, and heavy cream. Pour into the dry ingredients and stir until just combined, adding a splash bit more cream if the dough feels dry.

Turn out the dough onto a floured surface and gather into a semi-tight rectangle. Fold like a letter and flatten out again, using a rolling pin, into 1 ½” or so thick rectangle. Continue twice more then flatten once more.

Using a knife or bench scoop, cut into 8 squares or triangles.

Place the scones 1 to 2 inches (2.5 to 5 cm) apart on the baking sheet. Brush with heavy cream. Bake the scones until firm to the touch and golden, 18 to 20 minutes. Remove from the oven and transfer to a rack to cool.