1-First, caramelize the onions in butter over medium-low heat for 15 to 20 minutes until they turn deep golden brown, then let them cool.

2-Next, fry the bacon until it’s chewy, chop it into bite-sized pieces, and set it aside to cool.

3-Preheat your oven to 400 degrees Fahrenheit to ensure even baking.

4-Roll out the pie crust and press it into a deep tart or pie pan for a sturdy base.

5-In a bowl, whisk together the eggs, cream, salt, and pepper until smooth, then mix in the caramelized onions, bacon, and cheddar cheese.

6-Pour this mixture into the crust, place the pan on a rimmed baking sheet, and lightly cover with aluminum foil.

7-Bake for 40 to 45 minutes, remove the foil, and continue baking for another 10 to 15 minutes until the quiche is set and the crust is golden brown.

8-Finally, let the quiche rest for 10 to 15 minutes before slicing and serving. Overall, preparation takes about 30 minutes, with a total cooking time of 1 hour, making the whole process around 1 hour and 30 minutes.