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The first time I made these, I used a non-stick, metal, deep muffin tin. They rose dramatically (and stayed there) but were a devil to get out. This time, I thought I would try a silicone muffin 6 hole tray.
I thought of using the oil spray but changed my mind just in case. Instead, just 1 teaspoon of oil was added and the tray heated in the 220C oven (my tray can go to 240C). I didn't leave it in there long enough for the fat to smoke, but poured in the batter mix anyway (using 1/3rd of the recipe on my GF recipe tab above).
After 20 minutes they had risen well though not as high as in a metal tin and were duly served. Here they are from the side:
I think if I had let the oil get hot enough they might have risen more but still a good rise methinks!