Bring a large pot with salted water to a boil. Slice the ramp leafs into ribbons, cut the stems into pieces.
In a small sauce pan, melt the butter over low heat. Put the sage leafs in the hot butter and let them cook gently until they start to brown and look crispy. The butter will be brown and fragrant by now (do not let the butter burn!). Remove the pan from the heat. With a fork, remove the leafs from the pan. Let them drain on kitchen paper.
Let the butter cool off for several minutes (don't skip this step). Then whisk in the lemon zest, balsamic vinegar, and a good pinch of salt.
Cook the tortellini in the boiling water according to the instruction on the package.
Meanwhile, heat the olive oil in a large skillet and saute the ramps (leafs and stems) very, very briefly, until they are just starting to wilt. Season with salt and pepper.
Drain the tortellini, add them to the ramps together with the brown butter. Inmmediatly divide the pasta over deep plates and top with the crispy sage leafs, grated Parmesan, and, if you like, ramp flowers. Grind over some fresh black pepper, and squeeze over some lemon juice, if you like.