My grandmother was a fusion cook long before the term was even invented. She was born on the mainland and, in her 20s, moved to the United States, where she met my grandfather, married him and raised their eight children. Most of the food she cooked was traditional Chinese, of course, but she had a repertoire of four "Western" meals: roast beef and gravy, which she served with white rice; turkey with stuffing and gravy and white rice; pot roast with white rice; and fried chicken with spaghetti and tomato sauce. Until I moved away from home to go to university, I didn't realise these were unusual pairings - I thought everybody ate spaghetti with their fried chicken, and that white rice - not potatoes - was the usual accompaniment to roast beef.
But it wasn't these combinations that made my grandmother's cooking "fusion"; it was the fact she added Chinese ingredients to her Western food. Like the best fusion food, it was subtle. If she poured a glug of soy sauce into her pot roast and roast beef gravies, it wasn't obvious - it just deepened the colour and flavour. When she made turkey gravy, she added a small piece of chun pei (dried tangerine peel). It has a strong flavour, but she used such a small amount in such a large batch of gravy (she cooked Thanksgiving and Christmas lunch for about 40 people) that the only reason we knew the ingredient was in there was because my grandfather liked to fish it out of the pot and eat it.
My repertoire of non-Chinese dishes is vastly larger than my grandmother's, but I often follow her lead. I season long-simmered dishes and meat marinades with soy sauce and/or Vietnamese fish sauce, using them in addition to salt. The bottled sauces don't just add saltiness, they also have richer, more complex flavours than salt, and are very umami (the meaty savouriness known as the "fifth taste", a joining of salty, sweet, bitter and sour). Also rich in umami are dried Chinese mushrooms, which I add to beef bones when making broth, and which, if used judiciously, should be impossible to detect in the finished product.
Fusion food often gets a bad rap, but that's because some cooks misuse ingredients they are unfamiliar with. I'm certain my grandmother didn't consider what she cooked to be fusion food - all she knew was her additions made good food taste better.
Truc (tryk): noun, masculine, trick, gimmick, device. A French word for a chef's secret.