diff --git a/packages/evm/src/types.ts b/packages/evm/src/types.ts
index 7ecd0a27d7..9f899c641f 100644
--- a/packages/evm/src/types.ts
+++ b/packages/evm/src/types.ts
@@ -350,7 +350,7 @@ export interface EVMOpts {
   /**
    * Must be present if consensus type is clique/poa, else error will be thrown
    */
-  cliqueSigner?: Function
+  cliqueSigner?: (header: any) => Address
 }
 
 /**