I've always found my problems to be how to clean the trangia pans when out in the wild.
I always start my camping day with a couple of packets of Oatsosimple, Golden syrup, The berry one or the apple one all mixed up. The problem is then how do you clean out the oatmeal residue from the trangia pan/bowl. A few years ago, I started just boiling water in the porridgey pan, and then making tea with it. So it's tea with several lumps of oatmeal floating around in it. Some of my more sensitive friends find the concept of drinking tea with lumps in it quite disturbing. However the tea really does lift off the stubborn bits of oatmeal stuck to the pan.
If we dont' have sugar with us, I'm often found smashing a Werther's original to mix into my tea.
Sod it, I need to go camping.