Heat a pan over medium heat and add the butter and water.
When the butter water mixture is melted and sizzling add the peas.
Cook the peas for about 8-10 minutes, stirring occasionally, until softened.
Using a masher (or food processor, or spoon, or fork) mash the peas. Then stir in the lemon juice, lemon zest, salt, and pepper.
Drizzle the bread with olive oil and broil for a few minutes until toasted. Watch carefully as they can burn quickly!
Serve as 4 larger toasts or cut each in half to make 8 smaller halves.