I had an interesting sandwich the other day. It was tuna spinach wrap but mixed with a mustard blend with a smidgen of capers. Needless to say, it was quite savory. Was there anything I could have told the chef to add (rather than remove) to reduce the savoriness of the dish?
Savory usually means spicy & salty.
If you wanted to cut the sharp salty taste of the mustard & capers you could have used a 'sweet mustard' preparation.
I'm not sure if the spinach in the 'tuna spinach wrap' was actually leaf spinach or one of those green 'wraps' like a tortilla? Spinach has a bit of a metallic taste that some people find sharp. Switch to a mild lettuce like Romaine or even ice berg to offset such strong flavors as tina, mustard, & capers.
A bland cheese or mayonnaise can also help balance too much sharpness or 'tang' also.
It sounds as though the distinct caper and tuna flavors were too much for your palette. It is also possible that, smidgeon or not, there was too much of either. If I were you and returning to the same place I would try to cut the flavors