your thinking of giant EE Alocasia X odra X azurea.it gets about 10-12 ft high.in a shady moist spot.I had to search my book.I knew I had wrote down.that one has a blueish cast to the leaves.and its fragrant.the green ones flowers
are not fragrant.grows in tropical areas.has to be kept above 40 degrees.would look good with giant crinuim lilly amabile its a 4 ft tall pink spider lilly plant
(on my wish list) any way....xanthosoma saggitifolia has 2 ft tall leaves that are 20 inches wide.I've seen it grown in 25 gallon containers for zones
colder than a 7.
You may try a search for rain foest plants
....and find other large plants