1 hour if I'm actually focused and typing it out (serious). Depends what its about though. In-class essays in English can be done in that time, maybe 50-100 words short if I hate the topic, while History essays can be 1500 in maybe just under an hour
1500 word essay that isn't a research paper and is on a topic I know something about. I'd say about 1.5-2 hours. I usually write bull**** 2-3 page papers straight through which takes about 30-45 minutes, and then spend about an hour or two bickering with myself over poor word usage/sentence structuring.