In a large saucepan, add the AP flour, rice flour, cornstarch, sugar, soymilk, and coconut cream. Mix thoroughly and heat on medium-high until it comes to a boil, continuously stirring.

Once boiling, add the mastic and vanilla (if using) and reduce heat to low. Simmer for 25-30 minutes, stirring occasionally to ensure there aren't any lumps.

Make sure to move to the next burning process quickly, as the pudding will set and may get lumpy the longer it sits.

Give the tray a quick wash with water right before starting to burn the pudding to make sure the bottom layer doesn't stick. Put the baking pan over a medium-heat burner and place 1-2 cups of the pudding mixture to cover the entire bottom of the pan. Make sure to wear oven mitts and move the pan around to ensure an even burn.

Use a metal spatula to gently scrape the top to inspect; this will let you see what's happening below the excess pudding. You're looking for a very deep brown, almost black, color all over. The entire process can take 15 to 30 minutes, depending on the level of heat and the material of the pan.

When finished, set the pan aside and add the rest of the pudding mixture over the burned pudding. If there are any lumps, bring the pudding in the pot back to a boil while vigorously mixing, or use an immersion blender. Let cool, then cover and refrigerate for at least 6 hours. Overnight is even better.

Cut the pudding into squares with a spatula, making sure to graze and lift from the very bottom. Serve each slice cold, burned bottom side up, and sprinkled with cinnamon if preferred.