Mix all of the ingredients, except for the lemon juice and lemons, together in a bowl or measuring jug.
Heat a large skillet or saucepan over medium-high heat.
Pour the sauce into the skillet.
As the sauce starts to simmer, use a whisk to stir the sauce to prevent any lumps from forming.
The sauce needs to come to a boil to activate the cornflour (cornstarch), which will thicken the sauce.
Once the sauce has thickened to your liking, take the pan off the heat.
Whisk in the lemon juice. Start by adding the juice of half a lemon, and keep adding more to taste.
Once you are happy with the Sticky Lemon Sauce, add the lemon slices. These are mostly to serve as garnish or decoration.
This recipe makes a lot of sauce so there is enough to drizzle over some steamed rice or vegetables. If you don't want a lot of sauce in this dish, remove half of the sauce and store it in the fridge for another time.