Jetpack compose DropdownMenu With rounded Corners

Question

Hello I can't figure out how to make a cut corners menu in jetpack compose 1.0.0-beta02. I tried wrapping the while menu with a surface but It didn't work.

    TopAppBar(
        modifier = Modifier
            .statusBarsPadding(),
        title = {
            Text(text = "Title")
        },
        actions = {
            var menuExpanded by remember { mutableStateOf(false) }

            IconButton(onClick = { menuExpanded = true }) {
                Icon(Icons.Default.MoreVert, contentDescription = null)
            }

            DropdownMenu(
                expanded = menuExpanded,
                onDismissRequest = {
                    menuExpanded = false
                },
            ) {
                DropdownMenuItem(onClick = {}) {
                    Text("Item 2")
                }
            }
        },
    )

Copy

Which gives me

But I need something like this, which is rounded.