Looks like a technical drawing board: small squares forming a nice grid.
Source We Are Pixel8
This was formed by distorting an image of a background on Pixabay.
Source Firkin
Has nothing to do with toast, but it’s nice and subtle.
Source Pippin Lee
A good starting point for a cardboard pattern. This would work well in a variety of colors.
Source Atle Mo
Abstract Ellipses Background Grayscale
Source GDJ
Used a cherry by doctormo to make this seamless pattern
Source Firkin
To get the tile this is based on select the rectangle in Inkscape and use shift-alt-i.
Source Firkin
Zero CC tileable bark texture, photographed and made by me. CC0
Source Sojan Janso
Prismatic Geometric Tessellation Pattern No Background
Source GDJ
Medium gray pattern with small strokes to give a weave effect.
Source Catherine
From a drawing in 'The Quiver of Love', Walter Crane, 1876
Source Firkin
An abstract texture of black metal pipes (seamless).
Source V. Hartikainen
You know, tiny and sharp. I’m sure you’ll find a use for it.
Source Atle Mo