Add peeled and sliced peaches to a bowl and sprinkle with sugar and lemon juice. Stir well to combine, then allow to rest for 30 minutes to an hour, stirring once or twice.

Drain peach juice into a measuring cup to get 1 cup of juice. Pour juice into a saucepan, then whisk in cornstarch. Cook on medium heat for a few minutes, stirring, until thickened.

Remove from heat then stir in butter, salt and almond extract.

Pour sauce over peaches in a large mixing bowl and toss gently to coat. Pour fresh peach pie filling into a baked 9'' pie shell, place a piece of plastic wrap gently on top and refrigerate for least one hour before serving.

Serve with whipped cream on top, if desired.