Melt butter in a sauté pan over medium heat. Add garlic, onions, red pepper and sage. Saute 6–7 minutes until veggies are soft.
Add sauteéd onions, garlic, pepper and sage as well as all remaining ingredients to a high speed blender.
Blend on high for 1-2 minutes until completely smooth (it should very very smooth, if it’s not– keep blending or turn up the power higher) Stop to scrape down the sides as needed. Taste test and add additional salt, pepper or lemon juice to taste.
Pour over cooked pasta and toss until combined. Heat on low until warm enough to serve. Be careful to not overheat or the sauce may separate a bit.
Top with extra parmesan cheese and fresh herbs if desired.
Notes
Full fat (4%) cottage cheese works best. Lower fat cottage cheeses tend to be less creamy and the sauce is more likely to separate when heated.