Fill a medium mixing bowl half way with water and add the lemon juice.

Peal the apples, remove the core, slice them into small pieces and place them in the bowl filled with water.

As you fill the bowl with the sliced apples, stir them to make sure they're covered by the water, this will prevent them from browning.

Once you peal and slice all the apples, drain them using a colander and then leave the apples in the colander for at least 10 minutes so that the excess water drains.

In a large skillett, over a low heat, melt the butter. Make sure not to burn the butter.

Add the brown sugar and mix it with the melted butter.

Add the apples, and using a wooden spoon, stir them so that they are mixed in with the butter and brown sugar. Increase the heat to medium and stir the apples for about 5 minutes or until they start to soften.

Place them once more in a colander for a few more minutes so that any excess liquid drains.

Your apples are ready to be added to your pre-baked crust (see instructions above) and you can finish baking your delicious apple pie.