First, preheat your oven to 325°F to ensure even baking. Start by making the caramel: heat 1 cup sugar in a medium skillet over medium heat, stirring constantly until it melts into a golden syrup, then pour it into a 9-inch round cake pan to coat the bottom and sides evenly. Let it harden while you move on.

1- Whisk 4 eggs in a bowl until combined and set aside.

2- Heat 1 cup whole milk and 1 cup heavy cream in a saucepan over medium heat until it reaches about 175°F, stirring occasionally.

3- Remove from heat and whisk in 1 ½ cups bittersweet chocolate chips, 2 tablespoons cocoa powder, 1 teaspoon vanilla extract, and 1 pinch salt until fully mixed.

4- Pour the chocolate mixture into a bowl with 14 ounces sweetened condensed milk and whisk to combine, then slowly and gently whisk in the eggs to avoid air bubbles.

5- Pour the flan mixture over the hardened caramel in the cake pan and cover tightly with foil.

6- Place the cake pan inside a larger roasting pan, pour 4-6 cups boiling water into the roasting pan until it reaches halfway up the sides, and bake for 1 hour.

7- Check if the center is slightly jiggly like jello; if it’s liquid, bake in additional 5-minute increments until set.

8- Cool at room temperature for 1 hour, then refrigerate for at least 4 hours, preferably overnight.

9- To serve, run a knife around the edges, place a plate on top, and invert quickly to release the flan. Slice and enjoy with the caramel sauce.