This thread is about whether I should use a 'silicone mat' or 'non-stick parchment paper' for macarons, tomorrow. The reason why I felt I needed to create this thread, rather than look at past discussions from other websites, is because, on this 'aluminium baking tray (42cm x 30.5cm x 2mm)', the 'silicone baking mat (38cm x 28cm)' has slight curves close to the lipped edges of the tray, which would disrupt the heat in the fibreglass mesh in the mat, as it wouldn't be fully in contact with the tray. This is new equipment, purchased from 'Amazon UK'. As you can see from the picture below, I have weighed down the corners with stainless steel cutlery; however, I'm not entirely sure if the silicone mat will still work, so I needed to ask. Alternatively, I can use Lakeland Non-Stick (silicone-coated) Baking Parchment, which I can cut to size and secure into place, with dots of macaron batter. I am familiar with all stages with the French Macaron recipe (e.g. meringue, macaronage, etc); however, I am planning to bake the macarons, one tray at a time (middle-shelf), at 150°C (300°F), in a fan-assisted oven, using a Rubbermaid Oven Thermometer, for 20 minutes, so there's no deflation (hollow shells) with opening/closing the oven doors to check if the macarons are baked fully. I am using this recipe (http://www.indulgewithmimi.com/the-best-macaron-recipe/). Any reply would be much appreciated. Thank you.