Possible Clues:

• Sentimentality becomes Electra
• It's well drawn in Wonderland
• Dark viscous syrup which cannot be crystallised
• Large plant containing messy lac, sticky stuff
• Electra translation is a refined product
• Syrup, molasses
• Large plant around a cold lake produces molasses
• Dark viscous syrup obtained during the refining of sugar
• Last of sugar in drink, then half of eclair wasted as sweet stuff
• Molasses is sometimes called black ____