This paper investigates cases of compounding in the heritage language American Norwegian (AmNo), where elements from Norwegian and English are mixed word-internally, e.g., hoste-candy ‘cough candy’, where the Norwegian item hoste ‘cough’ is combined with the English item candy. Norwegian and English create compounds in similar ways, but with certain important differences, e.g., the use of linking elements. Based on data from the Corpus of American Nordic Speech, we investigate the encounter of these two languages within one word and find that both Norwegian and English lexical items occur as both left-hand and right-hand members of mixed compounds. Moreover, these mixed compounds are generally accompanied by Norwegian functional items. Hence, we argue that the overall structure of mixed compounds in AmNo is Norwegian, and English lexical items may be inserted into specific positions. This is successfully analyzed in a DM/exoskeletal model of grammar. We show that our results are in line with what we expect based on previous accounts of AmNo language mixing and Norwegian compounds, and our specific focus on compound-internal mixing provides a novel perspective and new insights into both the structure of compounds and the nature of language mixing.