Recursive function gives me None result instead of boolean true of false

so i was playing around with python if else loop to deepen my understanding with recursion. But i had a problem with this particular one.

I have a list of 5 integers, and if there is any odd number in the list, change allEven boolean logic to False. But however, my current code returns me None instead.

def areEven(l):
    if len(l) != 0:
        
        if l[0] % 2 == 0:
            allEven = True
            l.pop(0)
            areEven(l)
        else:
            allEven = False
    else:
        return areEven(l)

print('All are even is',areEven([2,4,6,8,11]))

Is there something wrong with this code, or is it me that understood recursion wrongly?(Note that i can only use a if else statement and not any other loops)