Core and slice the apples. Cut into medium sized chunks.
Transfer to a saucepan with the brown sugar and cinnamon. Cook on low heat for 5 minutes.
Add the butter and lemon juice and mix well. Continue cooking for 10 more minutes, mixing occasionally.
Once the apples soften a bit, take the saucepan off heat and allow the apples to cool down. Serve or store for later.
Notes
Want to cut down the cooking time further? Chop the apples into even smaller pieces.
Start with a little sugar, taste and add more if needed. This is especially true if you're starting with a sweeter variety of apples.
The cooking time will depend on the size of your apple chunks and how you prefer the final texture. If you want the stewed apples to be softer, keep cooking them for a few extra minutes.
You can also add a bit of cornstarch, arrowroot powder or tapioca starch to thicken up the mixture.