I’m currently working on a more complex project that uses double sided assembly (and a weird USB-C connector). To practice these things a little, I ordered some low cost boards to get used to that connector and explore double sided reflow (which seems easier than I expected).
For those who are interested, this is a reference design from framework computer for their expansion card system. It can be programmed with circuitpython or Arduino and utilises a SAMD21 microcontroller.
I used a Chinese oven that looked just like that, maybe the same model. I found it uneven in its heating, so much so that paste near the door sometimes didn’t flow. It was possibly a step up from my Black and Decker toaster oven.