Danes are teased for sounding like they're talking with a potato in their mouth

Swedes and Norwegians can often read Danish without much trouble, since the written languages are closely related, but understanding it spoken is another matter — hence the running joke that Danish sounds like Swedish spoken around a hot potato. Danish has swallowed many of its consonants over centuries of sound change, turning crisp written spellings into a heavily softened stream of speech that studies show trips up its closest linguistic relatives more than the reverse.

— Wikipedia contributors, Comparison of Danish, Norwegian and Swedish — North Germanic languages