Translation:I have tried to cut the bread for you.
Ah, I found the answer: the simple past tense is prøvede, but all perfect forms are prøvet. Jeg prøvede at lære dansk - I tried to learn Danish [and then stopped] Jeg har prøvet at lærne dansk - I have tried to learn Danish [and am still trying]
So a simple rule would be: if there is a har, havde, or have in front: it's "prøvet", otherwise: "prøvede".
Full conjugation map here: http://www.verbix.com/webverbix/go.php?D1=26&T1=pr%C3%B8ve&H1=126