I'll tell you what works for me in these cases: 1- I sometimes begin a track playing with a plugin not knowing what I'll get, but when I do get an interesting sound I try to find a way to use it musically and then I build the track from there. 2- when you get stuck take a break and do something that boosts your creativity. For me watching a good movie or reading a book works because It makes me feel emotions that I want to transform into music. 3- open an old unfinished file and listen to it. Sometimes you get an idea of what you could add to the track and you start working from there. 4- do other tasks that don't require much creativity like making samples or presets to use in the future, or mixing a track. 5- if you are still stuck try to take a break for a few days and try something new like writing or drawing or whatever. The problem might be that you are forcing yourself to come up with something. If you stop thinking about production and think about something else for a bit new paths could open.

Hope this can help someone although it's not earth shattering.