Pour the oil into a large frying pan placed over medium heat, then place the chicken flat in the pan, skin-side down. Put the brick on top of the chicken, and give it a firm press to make sure the skin is as flat as possible on the frying pan. Cook the chicken this way for 10-12 minutes on one side, checking the bottom at the end of the cooking time to make sure the skin underneath is completely golden and crispy. If the skin is still limp at this point, you can fry it for another 3-5 minutes. Then, when the skin is sufficiently crispy, remove the brick and flip the chicken, turning it on the flesh side for 2 minutes just to finish off the cooking. When done, take the chicken out of the pan and let it rest on a plate or tray.

To make the pan sauce, in the same pan the chicken was cooked in, add the butter and lemon juice, swirling the pan around to help release the brown bits of chicken skin stuck onto the pan. Put the pan back on medium heat, then add sugar, salt, and chicken stock. Bring this to a boil while stirring it. Then, in a small bowl, whisk together the cornstarch and 1 tbsp of water, and then pour it into the pan as well. Stir to combine until the sauce is thick. Then strain the sauce into a bowl.

The chicken is great on its own with a bit of sauce, and should be eaten quick, lest the skin will turn un-crispy. Also just as an extra suggestion, I love making a meal of it with a scoop of rice and a simple leafy salad.