My older brother gave me a pair of large Golden Gouramis because he found them boring.
I put them both in a 50 or so litre tub as that was all I had, with a hollow log, IAL and peat. I fed them on frozen bloodworms and brineshrimp and within a few days they had spawned. Unfortunately, I had to cull their fry as I had no resources or time to deal with them.
My water is extremely soft so I assume that helped things along, the humidity was also very high, and the water level low compared to most standard tanks. The plastic was also opaque, which provided the pair with some privacy.
They are now living in a community tank at his girlfriend's house, and I don't believe they have spawned since.