Decide what you’re making: dip/sauce (needs spoonable thickness), baking (needs smooth texture), or batter (can be slightly looser).
Start with the closest match from the ingredient list and use the listed ratio as your baseline.
If your substitute is thicker than fromage frais, loosen it with 1–2 teaspoon milk at a time; if it’s looser, reduce by draining or simmering (for sauces).
For baking, warm the substitute to room temperature and mix gently to reduce graininess or curdling.
Taste and adjust acidity: add a tiny splash of lemon juice for extra tang, or a pinch of salt to boost overall flavor.