What i can say is that, the more you let her eat on her own, the better she will eat in ling run.
I've seen a similar problem with a little one in my family. Since u say her age is 2.5 this could be teething problm. Thts wat happend with us. The first teeth came out fine bt she started having alot of problm at 3. She stopped eating n despite not eating started having upset stomach. She also used to hold her head as if having headache. We visited the dr.who told us tht teething is the problm. Gave her gripe water regularly n gave her cold food. Milk shakes n home made juices. More liquid diet with minimum spices. also the dr. gave something to rub over gums to help in the pain n itching. You can try to press her gums with ur fingers to knw if thts the problm. Also u can visit a dr. once to make sure tht she has no infection in her stomach.
Hope this can help n ur little one gets out this trouble soon. All the best.
tryout something new. sometimes kids get bored of repetitive things. chk pristine first bite beginings in corn/wheat/ other flavors.
you can get it on firstcry.com
also tryout some new recipes upma/poha/pav-bhaji etc