Glad about the phone call..
but now you've gone and done it. I started looking up open faced sandwiches on google image and now I'm very hungry.
This one would not be to everyone's taste, but gives me ideas -

Ingredients
1 trout fillet, 300g, one big piece or 2 fillets
bay leaf , 3 peppercorns and a dash of white wine vinegar for poaching
1 bunch of watercress , roughly chopped (save some sprigs for serving)
4 slices of sourdough bread or crusty bread, lightly toasted
4 tbsp mayonnaise , mixed with 2 tbsp creme fraiche, 1 tbsp lime juice and some seasoning