There are some Handyman Tradesman but I usually suggest you use those by referral/reputation. I would start with a plumber and they may refer you to a HVAC in the event you have some duct work leaking via condensation.
Condensation was on the list of possibilities. The spot is directly below the cooktop fan. The weird thing is why it's never done this before. It's been super humid here many, many times...why build up so much condensation now?