The thing that put me off for the longest time was the cost. Each time I endeavoured to make something like cupcakes, I would be horrified at the price of buying cocoa powder, icing sugar, butter, large eggs, all the different leavening agents, decorations and cupcake holders! But here’s an exhaustive, but basic, guide to the stuff I think you need:
To be stocked in your pantry at all times:
baking powder and baking soda
soft light or dark brown sugar
a loaf tin, round tin, brownie pan, and muffin tray
In terms of ingredients, the supermarket brand and bigger names are pretty much the same in quality for me. The only thing I would suggest going ~fancy~ for is vanilla extract because you can really tell the difference. Of course, you can adjust the list accordingly — if you’re on a mission to make Instaworthy unicorn cakes from the get-go, you’ll need more decorating stuff, but if you’re planning on making Victoria sponges, the stuff above should definitely suffice.