In 1812 he was recalled to Stuttgart, but soon left for Italy, where he continued his studies and met the Danish architect Peder Malling [da] (1781–1865).

It was Malling who in 1815 inspired Hetsch to come to Copenhagen, where he taught at the Royal Danish Academy of Fine Arts.

[2] One of Hetsch's first major projects was the interior decoration of the rebuilt Christiansborg Palace, where Christian Frederik Hansen was the principal architect.

Though most of his accomplishments were in the area of decorative art, Hetsch also designed the Great Synagogue (1833) and St. Ansgar's Church (1842) in Copenhagen.

[3] In parallel with his duties at the academy he held several other positions, including that of artistic director of the Royal Porcelain Factory (1828–1857).