Decide your use-case: gratin/baking (needs slow, creamy melt) vs. sandwich/topping (needs easy melt and sliceability).
Start with the 1:1 substitute ratio listed; use shredded/sliced cheese to reduce uneven melt.
If your swap tastes flatter (common with mozzarella/provolone), add a pinch of nutmeg, black pepper, or a small splash of vinegar to mimic emmental’s nuance.
If your swap looks too greasy, reduce cheese thickness or bake time slightly so it melts without pooling.
Taste and adjust at the end: salt carefully, and if you’re serving cold, let the cheese sit 5–10 minutes for fuller flavor.