You don't need paste for a QFN Package. Just tin the pads with your regular iron and solder, maybe add a bit of flux if you have, heat up the pad with hot air (~20s 10-20mm distance, based on heat output), place the chip (keep heating) and then when the solder is melted, squish down the chip with tweezers. It will push excess solder to the outside, making small balls out of it. Touch up the pins from the side if needed and done. Works better with lead solder, and if you have temperature control for the hot air, it's even better.
You can easily solder QFN with those 2000W heat guns that are sold for 30 EUR.
I think once I'll try doing it with a hair dryer just for the giggles.