Well, bread slices with butter (and optionally cheese) were referred to as "in the Dutch manner" in late medieval England. The North Germans sometimes called it "Frisian style". Late medieval/Early Modern German adopted the term "Butterbrot" for slices of bread with butter and just about anything else between, and it spread at the very least to Russian. I could see sandwiches being referred to as "Dutch bread" or "butterbrots", (for short "Dutchies" or "'brots"), in English, depending on the time and manner of adoption. Faux conoisseurs of Continental food will insist on pronouncing it with the proper laryngal R and long,open O, and endlessly debate the virtues of mixed grain wholemeal versus Rhenish rye bread and Westphalian ham, but most folk would still be happy with a chicken tikka masala 'brot. Or tuna and sweetcorn. On wonderbread.