ਮੈਨੂੰ ਤੈਨੂੰ ਆਪਣੇ ਨਾਲੋਂ ਵੱਧ ਪਿਆਰ ਹੈ
(Mainu tainu aapne naalton vadh pyaar hai)
However, this phrase is not commonly used in Punjabi. It's more common to say something like:
ਮੈਨੂੰ ਤੈਨੂੰ ਬਹੁਤ ਪਿਆਰ ਹੈ
(Mainu tainu bahut pyaar hai)
This means "I love you very much".
You could also say:
ਤੂੰ ਮੇਰੇ ਲਈ ਸਭ ਤੋਂ ਵੱਡਾ ਪਿਆਰ ਹੈ
(Tu mere lai sabh ton vadha pyaar hai)
Which translates to "You are my biggest love."
It's always best to choose the translation that sounds most natural and expresses the sentiment you want to convey.