Dissolve the cornstarch in half of the milk.

Heat the other half of the milk with the lemon peel and cinnamon stick to infuse the flavors.

Remove the lemon peel and cinnamon stick.

Add the sugar and the cornstarch mixture to the infused milk.

Cook over low heat, stirring constantly, until the mixture starts to thicken.

Lightly oil a rectangular baking dish and pour in the thickened mixture.

Spread the mixture evenly in the dish and cover with plastic wrap, pressing the wrap directly onto the surface to prevent a skin from forming.

Chill in the refrigerator for at least 6 hours.

Remove the solidified mixture from the dish.

Cut the mixture into squares.

Beat the egg.

Coat each square first in cornstarch, then dip in the beaten egg.

Fry the squares in plenty of oil until they start to turn golden brown.

Mix sugar with ground cinnamon to taste.

While still warm, coat the fried squares in the cinnamon-sugar mixture.