More literal:
* Kisa ki fé mwa kontan? (kee-sah kee fay mwah kon-tan) - This is the most direct translation and means "What makes me happy?"
* Ki chouz ki fé mwa kontan? (kee shooze kee fay mwah kon-tan) - Similar to the above, but using "chouz" (thing) instead of "kisa" (what).
More idiomatic:
* Kisa ki donne mwa la joie? (kee-sah kee donn mwah la zhwa) - This means "What gives me joy?" and is a more poetic way to express happiness.
* Kisa ki me fé sentir bien? (kee-sah kee meh fay sen-teer bee-en) - This means "What makes me feel good?" and emphasizes a sense of well-being.
Ultimately, the best way to say "what makes me happy" in Cajun French depends on the context and your personal preference.