3. Prepare Jars
Set four (4-ounce) jars on a sheet tray. Place one strip of lemon zest and a bay leaf in the bottom of each jar. Add 2 ½ ounces (70g) of tuna cubes to each jar, along with another strip of lemon zest. Fill each jar with 35g of olive oil to completely cover the tuna, pressing the tuna gently down into the jar if needed.