Add all ingredients to a saucepan and heat over medium low. Cook covered, stirring occasionally, until apples are just tender, 5-10 minutes.
The apples should release a good amount of water as they cook down, but if your apples look too dry add a splash of water. The liquid should thicken and coat the apples when they're done cooking.
Serve warm or cool to room temperature, then cover and store in the fridge.
Notes
Apples: Use crisp, firm varieties like Pink Lady, Honeycrisp, Fuji, Granny Smith, etc. You can also mix and match more tart apples (like Granny Smith) with sweeter apples (like Fuji). You can peel them if you'd like but I usually don't.Sugar and Lemon Juice: You may need more or less depending on how sweet/tart your apples are, so adjust to taste.