Bottles for formula/cereal combo!!!

Cierra

My sons pediatrician recommended we add cereal to his bottles to hopefully help with his reflux, but I can’t find a bottle that lets it flow out right. I’ve tried the bottles I’ve always used, the avent bottles with the biggest size nipple, which has 4 small holes and that comes out too slow, it took him 45 mins just to finish 4oz because it kept putting him to sleep before he could even finish 1 oz and this evening I purchased the tommee tippee bottles that said they were specifically made for cereal thickened formula with the y nipples and that came out too fast and made him choke. So, does anyone have any recommendations for what I should use? I’ve also heard people feed them cereal with a spoon while also feeding them their bottle, has anyone tried this? If so how did you divide up the cereal and bottle ratio and how did it go? My son is turning 3 months on Sunday.