In a large mixing bowl, whisk together the 1 ¼ cups all-purpose flour and ½ tsp salt. Add the ½ cup unsalted butter cold cubes and use your fingertips or a pastry brush to work the ½ cup unsalted butter cold into the 1 ¼ cups all-purpose flour until the mixture resembles coarse, pea-sized crumbs. Work quickly to keep the ½ cup unsalted butter cold cold.

Drizzle in the 3 tbsp ice water one tablespoon at a time, stirring gently with a whisk after each addition, until the dough just comes together when pressed. It should not be sticky. Turn the dough onto a lightly 1 ¼ cups all-purpose flour dusted surface, form it into a flat disc, wrap in plastic wrap, and refrigerate for at least 15 minutes.

Preheat your oven to 375°F. Lightly grease a standard 24 cups muffin tin. On a lightly 1 ¼ cups all-purpose flour dusted surface, roll the chilled dough out to about 1/8-inch thickness. Use a 3-inch round cookie cutter (or the rim of a glass (Large)) to cut out 24 rounds, re-rolling scraps as needed.

Gently press each dough round into a mini muffin tin cup, easing it up the sides without stretching. The edges can be slightly rustic — they'll look charming once baked. Prick the bottom of each shell 2–3 times with a dipping fork to prevent puffing.

Blind bake the shells: press a small square of aluminum foil into each shell and fill with a pinch of dried beans or rice as pie weights. Bake for 8 minutes, then carefully remove the aluminum foil and weights. The shells should look dry and just barely set. Set aside while you prepare the filling.

In a large measuring cups or mixing bowl with a pour spout, whisk together the 4 eggs, ¾ cup heavy cream, ¼ cup whole milk, ½ tsp salt, ¼ tsp black pepper freshly ground, and ⅛ tsp nutmeg freshly grated (if using) until completely smooth and uniform.

Line a baking sheet with aluminum foil, extending it up the sides to catch grease. Optionally place a wire rack on top for better airflow and crispier bacon. Lay strips in a single layer — close but not overlapping. No oil or extra seasoning needed.

Set oven to 400°F. You can start bacon in a cold oven as it preheats, or wait until fully preheated — both work. Use an external meat thermometer if your oven runs inaccurate. Start checking at 14–15 minutes. Thin-cut: 10–14 min. Standard-cut: 15–20 min. Thick-cut: 20–22 min. No need to flip. Check every couple of minutes after the first check — overdone happens fast. Pull bacon just before it looks done; it keeps cooking for a minute or two off the heat.

Carefully pour or ladle the 4 eggs custard into each shell, filling them about three-quarters full (roughly 1 tbsp each). Leave a little room at the top — the custard will puff slightly as it bakes. Sprinkle a few chopped fresh chives finely chopped on top of each quiche.

Bake at 375°F for 15–18 minutes, until the custard is just set with a very slight jiggle in the very center, and the tops are lightly golden. Do not overbake — the residual heat will finish setting the custard as they cool.