Many more words with doubled consonants can be created by adding vowel suffixes to shorter words e.g. hop-hopping, spin-spinner. This is just a sample.

After aAfter eAfter iAfter oAfter u as in punnetAfter u as in pudding
abbess
abbot
addict
address
affect
affix
aggress
allot
ally
amass
annex
annoy
annul
append
apply
assent
assess
asset
assist
assume
atoll
attach
attack
attempt
attend
attract
ballot
barrack
basset
batten
cannon
cannot
carrot
carry
channel
chattel
daffy
dally
dazzle
fatten
flatten
flattest
gallant
gallon
gallop
gannet
gladden
goddess
haddock
haggis
hammock
happen
jazzy
madden
maggot
mammal
mammoth
mapping
mattress
parrot
rabbit
rappel
rattan
sadden
savvy
snazzy
abbess
address
assess
begging
belly
berry
better
blessing
caress
cherry
confess
depress
dressy
dwelling
ebbing
effect
eggplant
eggshell
express
fennel
ferret
ferry
hello
impress
jelly
jetty
kennel
kettle
leggings
lemming
lessen
lesson
letters
lettuce
merry
messy
nettle
pebbles
pellet
pennant
penny
pepper
petty
process
profess
redden
reddest
reddish
rennet
settee
settle
shredded
sledding
spelling
stemming
teller
telly
tennis
undress
vessel
vetting
webbing
wedding
wettest
witness
yelling
amiss
biggest
billet
billy
bitten
brimming
chilly
chirrup
cirrus
dimmest
divvy
dizzy
drizzly
fibbing
fillet
filly
fizzle
fizzy
flippant
frilly
frizzy
gibbon
gimmick
griffin
grimmest
grizzly
hidden
hippest
hissing
iffy
immune
innate
innings
jiffy
kipper
kissing
kitten
mastiff
midden
mitten
pippin
quipping
quizzes
ribbon
ripping
ripple
shipping
silly
sitter
sizzle
skittish
skivvy
slimmest
slipper
smitten
sniffy
snippet
spiffy
stirrup
swizzle
tariff
tizzy
unpinned
unzipped
whippet
zippy
across
blossom
boffin
bonnet
bossy
bottom
brolly
coffin
collect
command
commend
comment
commit
common
commune
commute
connect
connive
connote
copping
correct
corrode
cotton
cutoff
dismiss
dissent
dobbin
dollop
dolly
emboss
folly
fossil
glossy
goddess
golly
gossip
gotten
grommets
hobbit
Holland
holly
hottest
nozzle
oddments
oddness
offal
offend
offset
oppose
oppress
pommel
popper
poppet
possum
prodded
ripoff
rotten
shopping
snobbish
sobbing
sodden
sonnet
sorry
tipoff
torrent
trodden
bubble
butter
buttocks
button
buttress
cubby
cuddle
currant
current
curry
fluffy
flummox
flurry
flutter
funnel
fussy
fuzzy
glummest
glutton
grubby
gullet
gully
gutted
hubby
juggle
muddy
muffin
mutton
nugget
plummet
puddles
puffin
puffy
pummel
punnet
puppet
rubber
rubbish
rubble
rudder
rugged
runoff
scrubbing
scurry
shudder
sluggish
smuggle
sputter
stubble
stubborn
stuffy
sudden
suffix
summit
summon
supper
supplant
supply
suppose
suppress
thudded
tuffet
tunnel
turret
upping
utter
bullet
bullock
bully
fully
hummus
pudding
pullet
pulling