Identify your dish: soup/sauce/braising usually wants body (broth) while baking often benefits from umami (miso/seasonings).
Pick the substitute that matches your flavor need, then apply the listed ratio in place of mushroom stock.
If the swap is weaker, simmer 3–6 minutes to concentrate; if it’s saltier (soy/miso), reduce added salt in your recipe.
Strain any mushroom-derived liquids (especially rehydration liquid) to avoid grittiness.
Taste at the end and fine-tune with acid (lemon/vinegar) to balance richness if needed.