removes broken link (#540)

"morter and pestle, of course" is linked to mortar-and-pestle.html, which doesn't seem to exist.

src/broiled-trevally.md

@@ -21,7 +21,7 @@ So here's a recipe to make it look---and taste!---more appealing.
 ## Directions
 1. Dice carrots, eggplant, squash, tomatoes and onions. Place these on a pan.
 2. Put basil, thyme, bay leaf, salt, and pepper on each of the fish's side. Place the fish above the veggies.
-3. Crush garlic and ginger (with [mortar and pestle, of course](mortar-and-pestle.html)) and place this in and around the fish.
+3. Crush garlic and ginger (with mortar and pestle, of course) and place this in and around the fish.
 4. Give it all a good splash of olive oil.
 5. Cover the pan and set to medium-low fire, until everything looks cooked.
 6. Flip the fish on the other side, just to make sure that it's properly cooked.