Extend the time delay of an asserted WDT active low
What you are looking for is called a monostable multivibrator. They exist in many formats. The 74xx121 is a typical example. Also a 555 timer can be used as such. For 60 seconds I think the 555 is well suited. Use a searchengine with 'monostable multivibrator' in image mode will give you lots of circuits.