Hofmann was a convinced modernist who stressed respecting the flat picture plane, among other articles of the modernist faith. His ideas regarding color might have been more useful for artists in general.
Below are examples of Hofmann's work, mostly over the last 30 years of his long career. Details on the Internet are sketchy, but it seems he was in Paris when the Great War broke out and was unable to return to Germany. Being an enemy alien, it is likely his life was circumscribed in some way, but I have no information regarding that. What one of the above sources mentions is that his paintings in Germany were lost, so there is little to document his early career. Oddly, I could not find much from the post-war German period either.
However, Hofmann was prolific, and there are paintings from the mid-1930s when he was doing his influential teaching that inspired many painters who became Abstract Expressionists in the 1940s and 1950s.
This is the only early Hofmann painting I found on the Internet.
A drawing with a jumbled-up view of the Riviera port, part of which is indeed on a hill.
Now we are in the zone when he was teaching in New York City and Provincetown on Cape Cod.
Cade Cod landscape of sorts. Hofmann often painted fairly thinly: Was the price of paint a factor during the Great Depression years?
Hofmann is said to have been influenced by Matisse, and this painting tends to suggest just that.
Here is a work that is fully abstract with lots of brushstroke expression. I imagine that this would have influenced those who later became the Abstract Expressionist school in New York.
He did not totally abandon representation until a few years later.
Again, vigorous brushwork, striking use of color and almost total abstraction.
The New York school of Abstract Expressionism was well into its ascendency when Hofmann painted this vaguely cubist work.
One of his last paintings. Very strong colors and composition. I'm not a big fan of Modernism, but I like this one.
During the 1960s Hofmann made a number of paintings that included rectangles. Perhaps he was interested in adding opposition to less-structured parts of these paintings.