Make me a pizza

Python 2, 202,198,190,177,162,157,146 bytes

n,t=input()
y=n+1
s=' '
l=' /'+'='*(n-1)+'\\ '+('','\n/'+s*y+'\\')[n>4]+'\n|'
print l+t[:y].center(y,s)+('','|\n|'+t[y:].center(y,s))[y%2]+l[::-1]

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Python 3, 224 213 195 bytes

n,t=eval(input())
k=n+1
y=print
i=0
f,s,e,b,p="/ =\\|"
t+=s*99
y(s+f+e*~-n+b)
if n>4:y(f+t[:k]+b);i+=k
y(p+t[i:i+k]+p);i+=k
if~-n%2:y(p+t[i:i+k]+p);i+=k
if n>4:y(b+t[i:i+k]+f);i+=k
y(s+b+e*~-n+f)

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