How can I incentivize users to perform creative tasks? Gamification is often used to incentivize people into performing small, repetitive tasks. For example, as a Stack Overflow user, I receive 2 reputation points for an accepted edit. I can earn badges by reviewing series of potentially problematic questions, etc. This seems to work fairly well since the user is given a reward for a easily achievable objective.

In contrast to this, what elements are required to incentivize users into performing creative tasks? Unlike with small 'assignments', a creative task bears the risk of not being solved satisfactory, therefore the user risks investing an effort without being rewarded.

Simply offering a higher reward introduces its own set of problems like having to deal with cheating, therefore my question:

How can I incentivize users to perform creative tasks (e.g., creating a new recipe)?
I think the methods you describe (i.e. those employed by Stack Exchange) work for creative tasks as well.

Asking good questions, and providing helpful answers can be considered creative. It's entirely possible that a user can put a lot of effort into an answer only for it to not solve the problem at all.

Whilst it can be disheartening when content isn't as good as you imagined, the feedback given (through upvotes and comments) allows you to improve upon what you've already produced, with the hope that it can be salvaged into something useful. This is essentially the benefit of gamification for sites like SE, by rewarding good content it encourages users themselves to improve and expand their knowledge - it's a learning experience.

So if a user is put off from submitting a recipe because they fear the community will react negatively to it, then maybe it was never very good to begin with.