Chocolate Orange Squares

Fix the parchment at the corners with small dabs of butter so it doesn't slip when you spread the batter.

Use truly room-temperature butter so the mixture becomes airy more quickly.

Occasionally scrape down the bowl with a spatula to ensure everything is evenly combined.

Toss the candied orange briefly in a little flour so it is distributed more evenly in the batter.

First mix it with a small amount of milk, then add the rest to achieve an extra smooth result.

Stir only as long as necessary so the squares stay tender.

A slightly moistened spatula or the back of a spoon makes it easier to smooth the batter.

Near the end, do a skewer test: only a few moist crumbs should cling to the skewer.

For best results, lift it off the sheet with the parchment and cool on a rack so it doesn't steam.

Use a large, sharp knife and wipe the blade between cuts for clean edges.

A light dusting of powdered sugar or a chocolate glaze with some orange zest works well.