The informal U.S. phrase to beat the Dutch means to do or say something remarkable or startling. It is often used as that beats the Dutch, meaning that beats everything.

Now used with reference to the Netherlands and their people, the word Dutch was formerly used in the general sense of German, and is related to the German word Deutsch, meaning German—cf. High Dutch, denoting unintelligible speech.

The word Dutch occurs in a number of English phrases, mostly with derogatory or derisive implications. These unfavourable associations sometimes have their origin in the rivalry and enmity between the English and the Dutch in the 17^th and 18^th centuries (cf. Dutch courage), but some of these phrases first occur later and originate in American-English use, and the precise underlying notion in the choice of Dutch is not always clear.

This is the case with to beat the Dutch. The earliest occurrence that I have found of this phrase is from the words of the following song, published in The Essex Journal and New-Hampshire Packet (Newburyport, Massachusetts) of 22^nd December 1775:
—Context: This song was composed, about the 14^th of December 1775, during the Siege of Boston. The Siege of Boston was the eleven-month period, from 19^th April 1775 to 17^th March 1776, when American militiamen effectively contained British troops within Boston, and after the Battle of Bunker Hill, to the peninsula of Charlestown.  The American, or Provincial, armed forces were initially called the New England Army (formed from the militiamen who answered the alarm on 19^th April 1775) and then became part of the Continental Army when it was established in June 1775:

Parnassian Packet.
A New Song.
Composed by a Soldier in the Continental Army.
[To the tune of the Black-Sloven.]

Tho’ some folks may tell us, it is not so clever
To handle a musket in cold frosty weather;
By yonder bright Congress * ¹, in spite of all such,
I’ll tarry this season, and take t’other touch.

Let poltroons and tories ² retire from our lines,
We’re stronger without them above fifty times:
Their infamous characters none will begruch,
Who tarry with us, boys, to take t’other touch.

Tho’ Haldimand, Gage, and the big talker § ³ too,
Think rusty old pork and our sauce will not do;
My brave fellow soldiers, we can’t think it much,
On the strength of roast beef, to give Howe t’other touch.

Our raiment, provision and pay, is quite good;
We’ve sea coal from Scotland ⁴, and plenty of wood:
How the country must laugh, if our folly is such,
As to let the militia obtain t’other touch.

Shall they have our posts, when we’ve all the works done,
Who for them ha’nt labour’d—no none of this fun:
I’ll see next campaign out—if it’s on a cruch;
And here’s to the lads, who will take t’other touch.

When North by brave Manley has sent, one wou’d think,
A vessel ⁵, whose bottom had all we want in’t;
Do ye think I wont stay when the prizes we clutch?
Yes, faith, that I will—and so here’s t’other touch.

The conquering Gen—, I’ve forgot his hard name,
Has made Fort St. John, and Chamblee very tame;
And Montreal also—’twill sweat Bute and Hutch—
When they here that Quebec to has got t’other touch.

And besides all the mortars, bombs, cannon & shells,
And bullets and guns—as the news-paper tells,
Our cargoes of meat, drink & cloaths beat the Dutch:
Now who wou’d not tarry, and take t’other touch?

* The Mortar so called.
§ Alluding to Burgoyne’s speech and letter.

¹ Congress was the name of a 13-inch brass mortar, taken a little before from the British by Captain John Manley (c.1733-1793), an officer in the Continental Navy.
² Here, Tory designates a colonist who has remained loyal to the King.
³ “the big talker” refers to the British general John Burgoyne (1722-1792).
⁴ A ship had lately been brought in by Captain John Manley, one item of the cargo of which was 105 chaldrons of coal.
⁵ This alludes to an immensely valuable prize, the British brigantine Nancy, taken by Captain John Manley on the 29^th of November 1775; this brigantine was carrying a large supply of ordnance and military stores intended for the British troops in Boston.

The second-earliest occurrence of the phrase to beat the Dutch that I have found is from The Courier News-Boy’s complimentary Ode to his Customers—To the tune of Yankee Doodle and the Windham Bull-Frogs, alternatively, published in the Courier of New Hampshire (Concord, New Hampshire) of 2^nd January 1805:
—Reflecting on the past year’s events, this ode mocked Republicans’ prioritisation of economy, the avoidance of war, the gunboat-based navy, the purported riches of Louisiana and the growing power of the South:

And yet in many things, and such
As need no resolution,
I’m excellent—I beat the Dutch
In mending Constitution;
As you will see, (by cunning strife)
If matters don’t miscarry,
You’ll have a President for life,
In spite of Dick and Harry.