Power Query load from Dataflow is excruciatingly slow

Go into Power query:

1. Create a new dataflow connection using Power BI dataflows to that same table.
2. That will generate 3-4 steps, a SOURCE, and a few Navigation steps.
3. Open the Advanced Editor and copy those first few lines. Do NOT copy the "in" that will be on line 4 or 5
4. Go to your original and paste over those same first few lines. (make a backup of that code obviously)
5. At the end of the last line you copied in, you need to add a comma. It was the last line in the original so had no comma.
6. Line 5 (or whatever the first line of the original dataflow you didn't copy over, just make sure the table reference refers to the name of the step before. It will likely be the name of the table but without the underscore.

So say this is your original Power Platform dataflow:

let
    Source = PowerPlatform.Dataflows(null),
    Workspaces = Source{[Id="Workspaces"]}[Data],
    #"9c50e50c-bbe6-4c3a-b6cd-b2623250536c" = Workspaces{[workspaceId="9c50e50c-bbe6-4c3a-b6cd-b2623250536c"]}[Data],
    #"d4c8ee27-89ac-40b7-958f-c3e8e7c69759" = #"9c50e50c-bbe6-4c3a-b6cd-b2623250536c"{[dataflowId="d4c8ee27-89ac-40b7-958f-c3e8e7c69759"]}[Data],
    Products_ = #"d4c8ee27-89ac-40b7-958f-c3e8e7c69759"{[entity="Products",version=""]}[Data],
    #"Filtered Rows" = Table.SelectRows(Products_, each [ProductKey] > 1800)
in
    #"Filtered Rows"

This is the same dataflow but withthe Power BI dataflow:

let
    Source = PowerBI.Dataflows(null),
    #"9c50e50c-bbe6-4c3a-b6cd-b2623250536c" = Source{[workspaceId="9c50e50c-bbe6-4c3a-b6cd-b2623250536c"]}[Data],
    #"d4c8ee27-89ac-40b7-958f-c3e8e7c69759" = #"9c50e50c-bbe6-4c3a-b6cd-b2623250536c"{[dataflowId="d4c8ee27-89ac-40b7-958f-c3e8e7c69759"]}[Data],
    Products1 = #"d4c8ee27-89ac-40b7-958f-c3e8e7c69759"{[entity="Products"]}[Data]
in
    Products1

So I will copy the Source through Products1 lines into my original and it becomes this:

let
    Source = PowerBI.Dataflows(null),
    #"9c50e50c-bbe6-4c3a-b6cd-b2623250536c" = Source{[workspaceId="9c50e50c-bbe6-4c3a-b6cd-b2623250536c"]}[Data],
    #"d4c8ee27-89ac-40b7-958f-c3e8e7c69759" = #"9c50e50c-bbe6-4c3a-b6cd-b2623250536c"{[dataflowId="d4c8ee27-89ac-40b7-958f-c3e8e7c69759"]}[Data],
    Products1 = #"d4c8ee27-89ac-40b7-958f-c3e8e7c69759"{[entity="Products"]}[Data],
    #"Filtered Rows" = Table.SelectRows(Products1, each [ProductKey] > 1800)
in
    #"Filtered Rows"

That is it. All subsequent steps (Filtered Rows in my example) remain unchanged.

5min tops.

Don't forget to delete the newly created dataflow you used to generate the code, or it will load that into the model too. You just needed it to get the code.