Based on what I know of Imposter Syndrome and the Dunning-Kruger effect, it seems you’re at your most competent when you feel like you’re at your least.
I’m not sure how you come to that conclusion, even with the internet meme version of the Dunning-Kruger effect. In the meme version, the incompetent think they are most competent, but I don’t think it follows that the most competent would think they are least competent.
I would summarize the actual Dunning-Kruger effect as: people tend to think they are a bit above average, and actual skill factors in only slightly. Worth emphasizing that these results are over groups of people, and individuals have extreme variation.