diff --git a/packages/nitro/src/runtime/entries/lambda.ts b/packages/nitro/src/runtime/entries/lambda.ts
index e1e69c3f56..5e686f0481 100644
--- a/packages/nitro/src/runtime/entries/lambda.ts
+++ b/packages/nitro/src/runtime/entries/lambda.ts
@@ -1,12 +1,16 @@
-import type { APIGatewayProxyEvent, APIGatewayProxyEventHeaders, APIGatewayProxyEventV2, Context } from 'aws-lambda'
+import type { APIGatewayProxyEvent, APIGatewayProxyEventHeaders, APIGatewayProxyEventV2, APIGatewayProxyResult, APIGatewayProxyResultV2, Context } from 'aws-lambda'
 import '#polyfill'
 import { withQuery } from 'ufo'
 import type { HeadersObject } from 'unenv/runtime/_internal/types'
 import { localCall } from '../server'
 
-export const handler = async function handler (event: APIGatewayProxyEvent & APIGatewayProxyEventV2, context: Context) {
-  const url = withQuery(event.path || event.rawPath, event.queryStringParameters)
-  const method = event.httpMethod || event.requestContext?.http?.method || 'get'
+export const handler = async function handler (event: APIGatewayProxyEvent | APIGatewayProxyEventV2, context: Context): Promise<APIGatewayProxyResult | APIGatewayProxyResultV2> {
+  const url = withQuery((event as APIGatewayProxyEvent).path || (event as APIGatewayProxyEventV2).rawPath, event.queryStringParameters)
+  const method = (event as APIGatewayProxyEvent).httpMethod || (event as APIGatewayProxyEventV2).requestContext?.http?.method || 'get'
+
+  if ('cookies' in event) {
+    event.headers.cookie = event.cookies.join(',')
+  }
 
   const r = await localCall({
     event,
@@ -26,7 +30,7 @@ export const handler = async function handler (event: APIGatewayProxyEvent & API
 }
 
 function normalizeIncomingHeaders (headers: APIGatewayProxyEventHeaders) {
-  return Object.fromEntries(Object.entries(headers).map(([key, value]) => [key.toLowerCase(), value as string]))
+  return Object.fromEntries(Object.entries(headers).map(([key, value]) => [key.toLowerCase(), value]))
 }
 
 function normalizeOutgoingHeaders (headers: HeadersObject) {