The challenge is "one layer".
That might sound daunting to some but honestly give it a try .
Some clever masking or embossing even distress inks can add lots of interest without any bulk.
For my card i stamped the butterfly from flutter by and then masked with a post it note.
Then using cracked pistachio and mermaid lagoon distress inks i blended the background.
I had also masked the card base so only the top corner was coloured.
I wanted to give a different look to the blended ink so added some perfect pearls.
I removed the mask and coloured the butterfly with prisma colour pencils.
The sentiment was stamped underneath and is from scripty saying stamp set.
To finish i added some dots of liquid pearls.
thanks for looking.