Using the xDai sidechain.
The xDai sidechain is a stable payments blockchain designed for fast and inexpensive stable transactions. xDai is used for transactions, payments and fees, and STAKE is used to support Proof-of-Stake consensus.
For anyone interested in experimenting with xDai before bridging tokens from the Ethereum mainnet, you can use the xDai faucet to claim 0.01 xDai (~ 1 cent) for free, which is enough to execute a few transactions on xDai. Anyone can top-up the xDai faucet balance.
Currently supports the transferring of DAI, USDC and USDT between the Polygon, xDai, Fantom and BSC mainnets.
Ensure that no matter what MetaMask sets your gas cost to, that you always set it to 1. xDai gas cost is always 1 Gwei, paying less than this it's unlikely your transaction will be accepted, paying more than this will waste xDai. The gas limit should typically be left as it is.