Agree with
@bucketnative that you need to give us more information.
BTW, I've had others' extract brews which have been excellent, so there's nothing endemic in extract that HAS to be bad. Instead, I suspect that the tendency of extract brews to have "that flavor" is more related to brewers' inexperience or errors, and not extract per se.
Here are several things you might work to improve (if you are not already doing them):
1. How's your water? My son used to brew extracts; when he switched to using RO (reverse osmosis) water, his beers took a leap forward. Your local water may or may not be a culprit here. For instance, is the water chlorinated and are you doing anything to offset that, if so?
- local london Thames tap water, so I expect it us chlorinated.
- what is ro water, is this the same as distilled?
2. Do you control fermentation temperature? Most brewers would probably tell you fermentation temp control was a huge leap forward for them. That is, with most ales you want temps during fermentation in the 60s. Yeast is exothermic, meaning it produces heat while it ferments the beer, and that can raise the temp of the beer 5 to 10 degrees above ambient temp. You can't go by what your room temp is, in other words.
- yes very much controlled in ny process explained in the post.
There are ways around this. You can use a ferm chamber (typically a refrigerator or chest freezer), even a swamp cooler to keep temps down. As most yeast rises in temps it starts to throw off off-flavors you don't want in your beer. There are a few exceptions to this (farmhouse or saisons, for instance), but mostly you want to control your fermentation temps.
There also is a style of yeast called Kveik ("Kwike") that isn't that sensitive to fermentation temps, producing good beer even up into the 90s. It's a liquid yeast, not the powdered yeast you're likely using.
3. How do you bottle? The enemy of beer after fermentation is oxidation, and this is especially the case with IPAs; the oxidation attacks hop aroma and flavor, muting it in a relatively short period of time. Are you doing anything that can limit oxidation?
- see process explanation
4. Is your equipment CLEAN and sanitized? Unlikely at this early point in your brewing career that you'd have an infection, but it's possible.
- definitely
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I'm a big believer in continuous quality improvement. That is, every time you brew, try to do something better. Over time, you'll approach that perfection you seek, never reaching it, but getting near.
Along those lines, I'd suggest brewing the same kit or style 2 or 3 times, trying to dial it in. If you change the kit or recipe every time, how can you tell if the problems are due to recipe or something else? You can't. I'd focus, if I were you, on dialing in a recipe, and only then branching out to other styles or recipes. The trick is to think about where you want to be in brewing six months from now.
I know that's hard. Lots to learn about in brewing, all this weird vocabulary (strike water, sparge, tun, pitch, mash, etc. etc.), and while it's not rocket science, it's not simplistic, either. It takes time to learn.
Of all the things brewers struggle to learn, the biggest one is....patience.
