First things first, it's essential to follow the instructions on the packaging, as different brands and types of pies may have varying cooking times. Generally, you can expect to cook a frozen apple pie in the oven at 375°F (190°C) for around 40-50 minutes, or until the crust is golden brown and the filling is bubbly. But, let's get into the nitty-gritty details, shall we?
For a conventional oven, you can typically cook a frozen apple pie for 45-50 minutes, while a convection oven may take around 30-40 minutes. And, if you're using a microwave, well, let's just say it's not the most recommended method, but if you're in a hurry, you can cook it on high for around 5-7 minutes, but be careful not to overcook it!