Close it up. Plan for skylight/solatube in the future if single level. Dark kitchens are no fun.

Close the window it will just scream addition

There no other windows near the kichen

Take out the window. Put in a skylight if you can.

Perhaps you could repurpose the window to the garage or laundry room to add yet more light there? (Preferably directly across from the opening.)

If a pass-thru would be useful at this point in the wall, you could add cabinet doors to cover the opening when not in use -- well worth doing, even preferable, if you have no other window in the kitchen.

Alternately, you could also have the doors not just doors but actual cabinets that swing open either into the kitchen or laundry room.

Alternately, you could build a cabinet in and through the wall at that point shelves that could be accessed from either the kitchen or laundry room.

Another option, my preference, would be to open up part of the wall and make the laundry room actually a part of the kitchen itself and the cabinets along this wall a peninsula and/or room dividing cabient, hiding any needed support posts for a weight bearing wall within and as a part of the new divider wall cabinet ... something like this:

[https://www.houzz.com/photos/sea-cliff-hideaway-traditional-kitchen-san-francisco-phvw-vp~57669[(https://www.houzz.com/photos/sea-cliff-hideaway-traditional-kitchen-san-francisco-phvw-vp~57669)

https://www.pinterest.com/pin/530369293587730721/

Make the countertop double depth and you could also use it as a bar and/or folding table from the laundry room side.

You could frame it out like mia suggested. I'd do that if the laundry room is very attractive so cabinets to keep supplies in for instance. Can a window be added on another wall is are all the walls interior?

I'd consider leaving the opening if the laundry room is going to be nice and kept tidy.

I'd close it up as I wouldn't want to look from one work area (the kitchen) into another (the laundry). Also, there is the noise and dust factor of the dryer.

We have both circumstances. Before we bought our house, a back porch had been enclosed to make a sunroom with windows on three sides. There is a picture window in the dining room, which gives us a view of the back yard through the sunroom (now mudroom) windows. It's unusual, but I would not give up that window.

A few years ago, we put an addition on the exterior kitchen wall, and took out the only window in the kitchen. In that remodel we framed the old window into a pass-through to the new room, a play room which doubles as a dining room for large family gatherings. There is a window in the addition, directly across from the pass-through, and again, I would not give up that borrowed view and the light it provides. How often will strangers come into your home (and even care about your window-to-the-laundry) compared to the light, and view, you will enjoy every day?

Without seeing the whole space hard to tell but probably could have done a better job of integrating the two spaces since I would have put the kitchen where you had a window and an outside wall

From someone who lived with a window over the sink looking into a room addition (done by a prior owner) ... it wasn't an ideal situation, but there were no other windows in the kitchen and like mamagoose, I preferred the light, view, and air it provided, even if borrowed from another room. When we remodeled the kitchen, we got rid of it and drywalled the opening, put in a big new window on another wall, and moved the sink under that window. I coudn't wait to get rid of that window and add another that actually looked outside rather than into another room.

We have an open concept living and kitchen area. We are taking out 2 windows and a set of double glass doors. We are moving the glass doors to another outside wall that has 2 other windows on that wall. The wall that will have the new doors and windows is opposite from kitchen about 15 ft away. The wall that the windows and doors were taken out of will be about 15ft wide.with no windows are doors