Gas Oven Question

The gas oven is putting off what appears to be full and even flame underneath, but it is taking forever to bring someting to temp. Any ideas why?

TIA,
Molo

Have you measured the gas flow? Light the burner and turn it up to max. Measure the gas flow for a minute or fifteen and compute BTUs per hour. Does it meet the oven spec? if not look at gas supply pressure and/or orifice obstruction.