Place a rack in center of oven and preheat your oven to 400°F

Heat a large cast iron skillet over medium heat and add a glug of oil. When it shimmers, add the onions and cook, stirring occasionally, 5–6 minutes until soft

Add the potatoes, and a pinch of salt. Cook for 5 minutes until the potatoes are beginning to get tender. Sprinkle 3 tbsp. of flour over the potatoes and cook, stirring constantly, until flour begins to stick to bottom of pan, about 30 seconds

Add the wine and cook, stirring constantly, about 1 minute

Add ½ pouch of Chimichurri, about 1½ cups of cream, the chicken, and a pinch of salt. Cook for about 5 minutes, stirring occasionally.

Place the skillet on a baking sheet

On a lightly floured surface, roll out the pastry into a square large enough to cover skillet with a bit of extra overhang. Then, roll up the pastry on the rolling pin and unroll it over the skillet

Fold the edges of pastry under itself and crimp the edges with a fork

Using a pastry brush, brush the top of pastry with a bit more cream and make a few small slits in the center

Bake until the filling is bubbling and pastry is puffed and golden brown, about 25 minutes