Since you posted in Extract forum, I assume you want all-extract?
My best 5-gal, partial boil, all-extract IPA to date (am currently working on modifying to PM/BIAB), all extracts obtained from morebeer:
3.5 gallons water in 5gal kettle
0.5# Crystal 40L (steeped at 150-160F)
Then add and boil 45 min (should lose ~0.25-0.5gal water altogether to boil):
2# Munich LME (50% Munich / 50% pilsner)
1oz Columbus pellets, 1oz Magnum pellets
Then add and boil 15 more min:
1# dextrose
4oz maltodextrin (for body, optional)
Clarifier (e.g., Whirlfloc)
At flameout, add:
6# Ultralight LME (100% 2-row)
1oz Columbus pellets (do a 30 min hopstand before chilling)
Chill to ~75F, add 2+ gal refrigerated top-off water (to ~5.25gal)
Pitch 11.5g packet US-05 at temp ~63-64F
Ferment 7-10 days at 64-65F, then raise to ambient/70F (or optionally rack to secondary) for 5-7 days
Dry-hop 5-7 days with: 1oz Simcoe, 1oz Citra, 1oz Amarillo
Bottle with ~3.5oz (100g) dextrose and (optionally) a clarifier like 5g gelatin
Let carbonate 2-3 weeks, then bottle condition another week or two
I come up with O.G. ~1.063, F.G. ~1.015, ~6.2% ABV, IBU somewhere around 50-55.
This is somewhat sweet and malty for an IPA, but that's what I wanted. I suppose you could use less Crystal or sub in 15L if you want less sweetness. I suppose you could swap out a pound of Munich for more Ultralight if you want less malty. The Munich does give a strong backbone, though, kinda like an old-school Pacific Northwest IPA, something kinda DeSchutes-ish, before everyone went all dryness / bitterness mad on IPA's.
I also find that if you cut out the bittering Columbus, cut the initial boil by about 15 min, and scale back the dextrose, this makes a pretty tasty APA with IBU I figure ~25-30.
Great citrusy nose, these hops do blend nicely. I think you could sub Zythos for the Amarillo and/or Simcoe, depending what's available. Gotta keep the Citra, though!
This was the first own-recipe I produced that my wife could find no flavor faults with--and believe me, she specializes in fault-finding! (IMO it does need more body, but that's part of why I'm going to PM/BIAB.)